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The death of rim brakes?
On Thu, 14 Mar 2019 17:13:37 -0400, Frank Krygowski
wrote: On 3/14/2019 4:39 PM, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs.* Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from.* Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere.* I think they were being serious.* Made it all the more laughable. Around here it's the extreme White Tailed Deer population. They are harming many other species in the forests by eating the entire understory. There are people who want to give them contraceptives instead of shooting them. I read somewhere that the population of white tailed deer in New Hampshire is actually higher today than it was in the late 1600's when the Pale Faces arrived. As for the use of contraceptives, think of the mental anguish of the poor female deer who cannot conceive. -- Cheers, John B. |
The death of rim brakes?
On Thu, 14 Mar 2019 16:22:10 -0500, AMuzi wrote:
On 3/14/2019 3:39 PM, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs. Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from. Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere. I think they were being serious. Made it all the more laughable. This is why we can't have satire now. Our government in its wisdom is airdropping immigrant (Canadian) wolves into Isle Royale National Park to decrease the overpopulated elk/moose. Suggestions for a high-ticket hunt were rejected despite great interest. Being eaten alive by wolves is so much more humane... Doesn't one require a sleigh and a troika for that? -- Cheers, John B. |
The death of rim brakes?
On 15/3/19 10:11 am, John B. Slocomb wrote:
On Thu, 14 Mar 2019 17:13:37 -0400, Frank Krygowski wrote: On 3/14/2019 4:39 PM, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs.Â* Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from.Â* Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere.Â* I think they were being serious.Â* Made it all the more laughable. Around here it's the extreme White Tailed Deer population. They are harming many other species in the forests by eating the entire understory. There are people who want to give them contraceptives instead of shooting them. I read somewhere that the population of white tailed deer in New Hampshire is actually higher today than it was in the late 1600's when the Pale Faces arrived. As for the use of contraceptives, think of the mental anguish of the poor female deer who cannot conceive. The male deer might be in terrible distress thinking he's firing blanks! -- JS |
The death of rim brakes?
On Fri, 15 Mar 2019 11:27:14 +1100, James
wrote: On 15/3/19 10:11 am, John B. Slocomb wrote: On Thu, 14 Mar 2019 17:13:37 -0400, Frank Krygowski wrote: On 3/14/2019 4:39 PM, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs.* Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from.* Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere.* I think they were being serious.* Made it all the more laughable. Around here it's the extreme White Tailed Deer population. They are harming many other species in the forests by eating the entire understory. There are people who want to give them contraceptives instead of shooting them. I read somewhere that the population of white tailed deer in New Hampshire is actually higher today than it was in the late 1600's when the Pale Faces arrived. As for the use of contraceptives, think of the mental anguish of the poor female deer who cannot conceive. The male deer might be in terrible distress thinking he's firing blanks! I'm not sure but I suspect that the Buck's attitude is " jump it and run" as I believe that the white tailed deer female is only receptive for a 24 hour period every year and a fellow needs to be fast on his feet :-) -- Cheers, John B. |
The death of rim brakes?
On Thursday, March 14, 2019 at 7:07:22 PM UTC-4, John B. Slocomb wrote:
On Fri, 15 Mar 2019 07:39:01 +1100, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs. Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from. Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere. I think they were being serious. Made it all the more laughable. My usual argument for the more obnoxious Environmental is to ask something like "Oh! Will you take a pair of wild pigs at your house". Their usual response, "Oh! The government's got to do that" to which I reply, "Are you willing to pay more in taxes to take care of the pigs?" The point is that most, if not all, of the devoted are not willing to actually do anything about what they are ranting and waving their arms about. -- Cheers, John B. I just love the environmentalists and animal lovers. Some of them re absolutely clueless. Many years ago I rescued and raised to racoon kits*. One of them used to climb up on me and wrap himself around my neck and go to sleep. He liked children and because of that I'd often take him to a nearby school to do a presentation with the children there. One cool day I was walking to the school and the racoon was wrapped around my neck and dozing. Some woman came up to me and started to berate me for having a dead racoon fur just to keep my neck warm. then she tried to grab the racoon fur and abscond with it. I still chuckle today when I recall the look on her face when the racoon hissed at her and her response, "Oh my God it's alive!" I told her not to be so hasty to judge things. Cheers * When I found the two racoon kits it was clear they were abandoned. Unfortunately I could not interest any of the animal welfare groups in our area to look after them and thus I was the one who raised them. |
The death of rim brakes?
On Thursday, March 14, 2019 at 3:58:47 PM UTC-7, John B. Slocomb wrote:
On Thu, 14 Mar 2019 10:07:53 -0700 (PDT), Sir Ridesalot wrote: On Thursday, March 14, 2019 at 12:59:35 PM UTC-4, Mark J. wrote: On 3/13/2019 4:36 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 16:07:48 -0700, "Mark J." wrote: On 3/13/2019 3:40 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 13:54:18 -0700 (PDT), Sir Ridesalot wrote: On Wednesday, March 13, 2019 at 3:17:05 PM UTC-4, AMuzi wrote: Snipped I don't get the obsession of reusing spokes. If that turns you on, fine. IMHO 'best rim for this rider/usage' can be severely limited by adding 'within poorly supported ERD'. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I don't think it's an obsession to use the old spokes. I think it's because many of us just like to tape the new rim to the old rim and then move the spokes to the new rim without having to unlace t he old wheel. Plus it saves a fair bit of money. Where I am shops cut spokes to length and t hen thread them. My understanding is that those cut threads make a weaker spoke than do spokes with rolled threads. I have a couple of extra wheels here that have tubular rims on t hem but the hubs and spokes are in excellent condition. If I could get a clincher rim to match the tubular rim so I could use the old spokes by taping the new rim to the old and transferring the spokes to the new rim I would. YMMV Cheers I see 14 gauge spokes with nipples listed on Amazon for $0.10 each in lots of 36. Please point me there! The lowest I can find on Amazon are ~$0.27 (US) each. I looked on Ebay and couldn't get anywhere near that price point. If they look reliable I'll use them to build wheels at a local non-profit / pro-bono community bike shop. Mark J. I couldn't find the site I originally quoted :-( But there were a number of sites offering spokes in sets of 36 for $10.00 or less. Given that the TREK bikes I see listed range from $11,799, with disc's, to $849, with conventional brakes, a measly ten bucks is chicken feed. For high-end Treks, sure. For functional recycled utility bikes that will be sold on a sliding scale or given away, not so much. The shop is sitting on a bunch of new donated rims, and it harvests hubs, many decent ones, from otherwise dead donated wheels. My goal is to turn those resources into working wheels through donated labor. Put it all together, and it's marginally competitive with complete wholesale wheels due to the cost of spokes. (And it's a fair question whether wheel building is an efficient use of donated skilled time.) My conjecture is that the rise of the boxed-wheels market has raised the price of spokes dramatically, as spokes' drop in wholesale/retail volume requires a much higher price to be worth stocking. I remember getting basic but name-brand spokes for 20 cents each, now it's closer to a dollar. Andy M., did I guess right about the market? Mark J. Where I am the bicycle shops don't stock different lengths of spokes. They cut and thread spokes to the length you want. Those spokes are a little over a dollar a piece Canadian. SO a 36 spoke wheel is at least $36.00 for new spokes. Add in the cost of a new rim and you can get a reasonable quality Alex rim wheel. That further lessens the demand for spokes. It's a vicious downward spiral. Cheers Two or three years ago I popped a couple of spokes in my rear wheel and didn't have any new spokes so went down to my local bike shop and bought a set of brand new Shimano wheels. For which I paid something like $50. I'm still using the wheels today and they still run true. Why in the world would anyone want to go to all the trouble of building a set of wheels :-) It doesn't pay if you're building a cheap wheel and don't own the parts. It pays if you own the parts and only need to replace a rim -- and it can really pay if you're building an expensive set of wheels. You can build a 28s wheel on, say, DT240s with a nice rim like a H Plus Son Hydra/HED Belgium and end up with something as nice as a HED Ardennes disc for half the price and maybe even less weight. Knock yourself out -- go with a CF rim. And it will be user serviceable using conventional parts -- no Zicral $5 spokes and threaded rim sockets. You can easily (or pretty easily) build a wheel that is light and durable as an expensive name brand. And if you don't build, even getting the local Bohemian wheel builder to do it isn't that expensive. Enve wheels, for example, are just Enve rims on nice hubs with good spokes. Our local wheelbuilder, Sugar, builds essentially the same wheel for slightly less. https://sugarwheelworks.com/ Now, if the Enve goes on sale, the price gap goes the other way -- but at least you supported a local business and some nice folks. -- Jay Beattie |
The death of rim brakes?
On 3/14/2019 5:58 PM, John B. Slocomb wrote:
On Thu, 14 Mar 2019 10:07:53 -0700 (PDT), Sir Ridesalot wrote: On Thursday, March 14, 2019 at 12:59:35 PM UTC-4, Mark J. wrote: On 3/13/2019 4:36 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 16:07:48 -0700, "Mark J." wrote: On 3/13/2019 3:40 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 13:54:18 -0700 (PDT), Sir Ridesalot wrote: On Wednesday, March 13, 2019 at 3:17:05 PM UTC-4, AMuzi wrote: Snipped I don't get the obsession of reusing spokes. If that turns you on, fine. IMHO 'best rim for this rider/usage' can be severely limited by adding 'within poorly supported ERD'. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I don't think it's an obsession to use the old spokes. I think it's because many of us just like to tape the new rim to the old rim and then move the spokes to the new rim without having to unlace t he old wheel. Plus it saves a fair bit of money. Where I am shops cut spokes to length and t hen thread them. My understanding is that those cut threads make a weaker spoke than do spokes with rolled threads. I have a couple of extra wheels here that have tubular rims on t hem but the hubs and spokes are in excellent condition. If I could get a clincher rim to match the tubular rim so I could use the old spokes by taping the new rim to the old and transferring the spokes to the new rim I would. YMMV Cheers I see 14 gauge spokes with nipples listed on Amazon for $0.10 each in lots of 36. Please point me there! The lowest I can find on Amazon are ~$0.27 (US) each. I looked on Ebay and couldn't get anywhere near that price point. If they look reliable I'll use them to build wheels at a local non-profit / pro-bono community bike shop. Mark J. I couldn't find the site I originally quoted :-( But there were a number of sites offering spokes in sets of 36 for $10.00 or less. Given that the TREK bikes I see listed range from $11,799, with disc's, to $849, with conventional brakes, a measly ten bucks is chicken feed. For high-end Treks, sure. For functional recycled utility bikes that will be sold on a sliding scale or given away, not so much. The shop is sitting on a bunch of new donated rims, and it harvests hubs, many decent ones, from otherwise dead donated wheels. My goal is to turn those resources into working wheels through donated labor. Put it all together, and it's marginally competitive with complete wholesale wheels due to the cost of spokes. (And it's a fair question whether wheel building is an efficient use of donated skilled time.) My conjecture is that the rise of the boxed-wheels market has raised the price of spokes dramatically, as spokes' drop in wholesale/retail volume requires a much higher price to be worth stocking. I remember getting basic but name-brand spokes for 20 cents each, now it's closer to a dollar. Andy M., did I guess right about the market? Mark J. Where I am the bicycle shops don't stock different lengths of spokes. They cut and thread spokes to the length you want. Those spokes are a little over a dollar a piece Canadian. SO a 36 spoke wheel is at least $36.00 for new spokes. Add in the cost of a new rim and you can get a reasonable quality Alex rim wheel. That further lessens the demand for spokes. It's a vicious downward spiral. Cheers Two or three years ago I popped a couple of spokes in my rear wheel and didn't have any new spokes so went down to my local bike shop and bought a set of brand new Shimano wheels. For which I paid something like $50. I'm still using the wheels today and they still run true. Why in the world would anyone want to go to all the trouble of building a set of wheels :-) Shimano are grey/black. 'nuff said! http://www.yellowjersey.org/fixrrec.jpg -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
The death of rim brakes?
On 15/3/19 2:17 am, Frank Krygowski wrote:
On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. -- JS |
The death of rim brakes?
On 3/14/2019 8:36 PM, James wrote:
On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. So a rear hydraulic disc is just as good as a fixed gear wheel (without the warped rotor thing). Check. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
The death of rim brakes?
On Thu, 14 Mar 2019 17:42:13 -0700 (PDT), Sir Ridesalot
wrote: On Thursday, March 14, 2019 at 7:07:22 PM UTC-4, John B. Slocomb wrote: On Fri, 15 Mar 2019 07:39:01 +1100, James wrote: On 14/3/19 3:54 pm, John B. Slocomb wrote: I read something to that effect the other day. Some sort of environmentalist site I think. I wonder what the tree huggers do when a cougar eats their pet dog :-) I think that is acceptable because ... nature. I'm not against environmental issues at all, just those who propose some "solution" without any thought at all. People that protest fox hunting while eating a McDonalds hamburger, for instance :-) There was something similar I read a little while back, about a Queensland politician who was photographed next to a pile of dead feral pigs. Apparently it is an annual event, to go shoot a heap of feral pigs, where he is from. Some city greens got all up tight about it and proposed that the pigs should be rounded up and sent to a pasture of their own somewhere. I think they were being serious. Made it all the more laughable. My usual argument for the more obnoxious Environmental is to ask something like "Oh! Will you take a pair of wild pigs at your house". Their usual response, "Oh! The government's got to do that" to which I reply, "Are you willing to pay more in taxes to take care of the pigs?" The point is that most, if not all, of the devoted are not willing to actually do anything about what they are ranting and waving their arms about. -- Cheers, John B. I just love the environmentalists and animal lovers. Some of them re absolutely clueless. Many years ago I rescued and raised to racoon kits*. One of them used to climb up on me and wrap himself around my neck and go to sleep. He liked children and because of that I'd often take him to a nearby school to do a presentation with the children there. One cool day I was walking to the school and the racoon was wrapped around my neck and dozing. Some woman came up to me and started to berate me for having a dead racoon fur just to keep my neck warm. then she tried to grab the racoon fur and abscond with it. I still chuckle today when I recall the look on her face when the racoon hissed at her and her response, "Oh my God it's alive!" I told her not to be so hasty to judge things. Cheers * When I found the two racoon kits it was clear they were abandoned. Unfortunately I could not interest any of the animal welfare groups in our area to look after them and thus I was the one who raised them. A friend had a whole tribe of pet skunks and if you were a country boy it would almost make your heart stop to see the mother skunk with a while parade of kittens walk out from under the couch. He also had a racoon, an old evil male (boar?) but he wasn't playful, in fact he would kill, or severely damage, a full grown dog if the dog attacked him. -- Cheers, John B. |
The death of rim brakes?
On Thu, 14 Mar 2019 19:53:38 -0500, AMuzi wrote:
On 3/14/2019 5:58 PM, John B. Slocomb wrote: On Thu, 14 Mar 2019 10:07:53 -0700 (PDT), Sir Ridesalot wrote: On Thursday, March 14, 2019 at 12:59:35 PM UTC-4, Mark J. wrote: On 3/13/2019 4:36 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 16:07:48 -0700, "Mark J." wrote: On 3/13/2019 3:40 PM, John B. Slocomb wrote: On Wed, 13 Mar 2019 13:54:18 -0700 (PDT), Sir Ridesalot wrote: On Wednesday, March 13, 2019 at 3:17:05 PM UTC-4, AMuzi wrote: Snipped I don't get the obsession of reusing spokes. If that turns you on, fine. IMHO 'best rim for this rider/usage' can be severely limited by adding 'within poorly supported ERD'. -- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 I don't think it's an obsession to use the old spokes. I think it's because many of us just like to tape the new rim to the old rim and then move the spokes to the new rim without having to unlace t he old wheel. Plus it saves a fair bit of money. Where I am shops cut spokes to length and t hen thread them. My understanding is that those cut threads make a weaker spoke than do spokes with rolled threads. I have a couple of extra wheels here that have tubular rims on t hem but the hubs and spokes are in excellent condition. If I could get a clincher rim to match the tubular rim so I could use the old spokes by taping the new rim to the old and transferring the spokes to the new rim I would. YMMV Cheers I see 14 gauge spokes with nipples listed on Amazon for $0.10 each in lots of 36. Please point me there! The lowest I can find on Amazon are ~$0.27 (US) each. I looked on Ebay and couldn't get anywhere near that price point. If they look reliable I'll use them to build wheels at a local non-profit / pro-bono community bike shop. Mark J. I couldn't find the site I originally quoted :-( But there were a number of sites offering spokes in sets of 36 for $10.00 or less. Given that the TREK bikes I see listed range from $11,799, with disc's, to $849, with conventional brakes, a measly ten bucks is chicken feed. For high-end Treks, sure. For functional recycled utility bikes that will be sold on a sliding scale or given away, not so much. The shop is sitting on a bunch of new donated rims, and it harvests hubs, many decent ones, from otherwise dead donated wheels. My goal is to turn those resources into working wheels through donated labor. Put it all together, and it's marginally competitive with complete wholesale wheels due to the cost of spokes. (And it's a fair question whether wheel building is an efficient use of donated skilled time.) My conjecture is that the rise of the boxed-wheels market has raised the price of spokes dramatically, as spokes' drop in wholesale/retail volume requires a much higher price to be worth stocking. I remember getting basic but name-brand spokes for 20 cents each, now it's closer to a dollar. Andy M., did I guess right about the market? Mark J. Where I am the bicycle shops don't stock different lengths of spokes. They cut and thread spokes to the length you want. Those spokes are a little over a dollar a piece Canadian. SO a 36 spoke wheel is at least $36.00 for new spokes. Add in the cost of a new rim and you can get a reasonable quality Alex rim wheel. That further lessens the demand for spokes. It's a vicious downward spiral. Cheers Two or three years ago I popped a couple of spokes in my rear wheel and didn't have any new spokes so went down to my local bike shop and bought a set of brand new Shimano wheels. For which I paid something like $50. I'm still using the wheels today and they still run true. Why in the world would anyone want to go to all the trouble of building a set of wheels :-) Shimano are grey/black. 'nuff said! http://www.yellowjersey.org/fixrrec.jpg Goodness! Don't you know that "Black is Beautiful"? -- Cheers, John B. |
The death of rim brakes?
On Fri, 15 Mar 2019 12:36:42 +1100, James
wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) -- Cheers, John B. |
The death of rim brakes?
On 15/3/19 1:50 pm, John B. Slocomb wrote:
On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. -- JS |
The death of rim brakes?
On Fri, 15 Mar 2019 15:24:05 +1100, James
wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. -- Cheers, John B. |
The death of rim brakes?
On Fri, 15 Mar 2019 11:57:26 +0700, John B. Slocomb
wrote: On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. As an addendum: While cheaper they do look a bit low budget so, as one might say, who would one want a $10 brake on a $3,000 bicycle... even if they do stop well :-) -- Cheers, John B. |
The death of rim brakes?
On 15/3/19 5:01 pm, John B. Slocomb wrote:
On Fri, 15 Mar 2019 11:57:26 +0700, John B. Slocomb wrote: On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. As an addendum: While cheaper they do look a bit low budget so, as one might say, who would one want a $10 brake on a $3,000 bicycle... even if they do stop well :-) I've had canti brakes on a MTB. Yes the rims took a hammering. -- JS |
The death of rim brakes?
Am 15.03.2019 um 02:36 schrieb James:
Are rim brakes good enough?Â* Sure!Â* They have been for a long time.Â* Are disc brakes better?Â* Yes I think so. Two facts pointing to the other direction: Rim brakes are lighter than dics brakes. Rim brakes dissipate heat better than disc brakes (but dics brakes dissipate heat better than drum brakes). For lightness, you might want small, thin discs, for heat stability you want the opposite. Discs that are too small or too thin can heat up so strong that they warp. |
The death of rim brakes?
John B. Slocomb wrote:
On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. And, of course, a disc brake is heavier than a rim brake :-) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. -- Cheers, John B. With cantis and V-brakes, you may still have to disconnect the straddle wire or deflate your tire to remove the wheel. And if the brake pads sit inside the fork, they will limit how wide of a tire you can install, while disc brakes won't. |
The death of rim brakes?
On Thursday, March 14, 2019 at 6:36:52 PM UTC-7, James wrote:
On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. |
The death of rim brakes?
On Friday, March 15, 2019 at 6:23:52 AM UTC-7, Ralph Barone wrote:
John B. Slocomb wrote: On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive.. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes.. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. |
The death of rim brakes?
On Fri, 15 Mar 2019 17:22:58 +1100, James
wrote: On 15/3/19 5:01 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 11:57:26 +0700, John B. Slocomb wrote: On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. (MUCH DELETED) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. As an addendum: While cheaper they do look a bit low budget so, as one might say, who would one want a $10 brake on a $3,000 bicycle... even if they do stop well :-) I've had canti brakes on a MTB. Yes the rims took a hammering. It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. -- Cheers, John B. |
The death of rim brakes?
On Friday, March 15, 2019 at 4:32:23 PM UTC-7, John B. Slocomb wrote:
On Fri, 15 Mar 2019 17:22:58 +1100, James wrote: On 15/3/19 5:01 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 11:57:26 +0700, John B. Slocomb wrote: On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: On 15/3/19 1:50 pm, John B. Slocomb wrote: On Fri, 15 Mar 2019 12:36:42 +1100, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. (MUCH DELETED) And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. As an addendum: While cheaper they do look a bit low budget so, as one might say, who would one want a $10 brake on a $3,000 bicycle... even if they do stop well :-) I've had canti brakes on a MTB. Yes the rims took a hammering. It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. My disc wheels haven't exploded so far, and I've been riding home-built disc wheels on cheap hubs (M525 or SP PD8 dyno) and relatively cheap rims (CR 18 or now out of production Velocity touring disc) for about 15 years. I even have a Vuelta el-cheapo disc that has held up well. I bought the first generation Cannondale CADDX CX bike with discs before they were UCI legal for cyclocross -- which is why I dropped out of racing CX as a pro in Europe. If they wouldn't accept my brakes, I wasn't going to race there. It has been my commuter for years, along with its replacement (yes, I broke the original frame -- broken frame number 7(? could be more)). My other bikes with disc wheels are doing fine, too. -- Jay Beattie. |
The death of rim brakes?
On 16/3/19 10:32 am, John B. Slocomb wrote:
It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. -- JS |
The death of rim brakes?
On Sat, 16 Mar 2019 18:57:21 +1100, James
wrote: On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. But they do built a rim brake wheel with radial spokes }-) I think that if I were riding around in the mud and mire I probably would want discs but I don't do that. Anywhere that I want to go has paved roads leading to it. I find it rather revealing that in 1880 the League of American Wheelmen, a bicycle advocate group, was formed and one of the first things that they lobbied for was smooth roads. Now that smooth roads, in the U.S. at least, probably make up the majority of the roads people have discovered riding out in the bush where there hardly aren't any roads at all. I suppose that the moral is that once a bicyclist finally gets something they immediately want something different :-} -- Cheers, John B. |
The death of rim brakes?
with John B Slocomb wrote:
On Fri, 15 Mar 2019 15:24:05 +1100, James wrote: *SKIP* And rim brake callipers that go around fat tyres often flex a lot and don't work so well. So disc brakes for fat tyre bikes are a better choice, and rim brakes for racing bikes with skinny tyres are pretty good. Don't use calipers. Try cantilever or the more modern Shimano V-brakes. They don't care how wide the tire is. Of course they (v-brakes) do. My success story. My prefered LBS (at the moment, they've changed their ways) had really brain-dead parking -- right triangle from side-view, with very narrow parking holes, with maybe 30cm height. My 700Cx49 just couldn't possibly fit in. What effectively disabled me from reaching (with 180cm cable) front wheel. So, one day, I park with this abomination, do my LBS stuff, unpark, and ride away. And then over each change in road's smoothness (natural or not) I detect some unusual sound. That made me wonder. At some point I had to go on a curb, so I was looking around front wheel and then,.. Holy Chain! As I lift fork I see front wheel droping out dropouts (quick-release had been involved), is blocked by v-brakes, hits a sidewalk, and is placed back into dropouts. I speculate that some random dude (with evil intentions) undid quick-release as this bike was parked and had found out he had to release v-brakes, then exhaust tyre, and only then he could possibly labour the wheel out (because neither releasing nor exhausting help much, these steps just enable). And getting real dirty on the way. That's how V-Brakes Save The Day! p.s. Also, example of proper quoting. -- Torvalds' goal for Linux is very simple: World Domination Stallman's goal for GNU is even simpler: Freedom |
The death of rim brakes?
James wrote:
On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. No matter what size of disc brake you have, the spoke forces are the same, since the braking force is applied to the hub, which then transfers it through the spokes to the rim/tire. In the limit, the hub is stationary and the wheel is sliding. In this case, the size of the disc determines how much tangential force is applied to the disc, but the force on the spokes is determined by the number of spokes, the lacing pattern and the hub diameter. |
The death of rim brakes?
John B. Slocomb wrote:
On Sat, 16 Mar 2019 18:57:21 +1100, James wrote: On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. But they do built a rim brake wheel with radial spokes }-) Certainly. But only for front wheels, since rear wheels have accelerating torque applied through the spokes, regardless of the braking method. I think that if I were riding around in the mud and mire I probably would want discs but I don't do that. Anywhere that I want to go has paved roads leading to it. I find it rather revealing that in 1880 the League of American Wheelmen, a bicycle advocate group, was formed and one of the first things that they lobbied for was smooth roads. Now that smooth roads, in the U.S. at least, probably make up the majority of the roads people have discovered riding out in the bush where there hardly aren't any roads at all. I suppose that the moral is that once a bicyclist finally gets something they immediately want something different :-} -- Cheers, John B. |
The death of rim brakes?
On 16/3/19 7:38 pm, John B. Slocomb wrote:
On Sat, 16 Mar 2019 18:57:21 +1100, James wrote: On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. But they do built a rim brake wheel with radial spokes }-) Yes, I use some I built. It's mostly a fashion thing. The weight reduction by shorter spokes isn't worth worrying about. In most cases a regular 3x spoke wheel is sufficient to transfer brake forces from the hub to the rim. Imagine the possible force on spokes possible from a 28 tooth chain ring to a 34 tooth rear sprocket? I think that if I were riding around in the mud and mire I probably would want discs but I don't do that. Anywhere that I want to go has paved roads leading to it. I find it rather revealing that in 1880 the League of American Wheelmen, a bicycle advocate group, was formed and one of the first things that they lobbied for was smooth roads. Now that smooth roads, in the U.S. at least, probably make up the majority of the roads people have discovered riding out in the bush where there hardly aren't any roads at all. Where I live there are hundreds of kms of gravel roads that are too rough for my road bike (I've tried). Where as my options are limited by bitumen only roads. Only the main connecting roads are bitumen, and they are high speed roads where drivers dislike passing cyclists safely. I think that people have realised that there are many unmade roads to explore, and there are few cars on them to worry about. -- JS |
The death of rim brakes?
On 17/3/19 2:56 am, Ralph Barone wrote:
I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. The spokes may not see any torque between the hub and rim, but are certainly forces due to braking that the spokes see. -- JS |
The death of rim brakes?
James wrote:
On 17/3/19 2:56 am, Ralph Barone wrote: I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. The spokes may not see any torque between the hub and rim, but are certainly forces due to braking that the spokes see. Now that I think about it some more, yes, there should be increased tension on the rear facing spokes and decreased tension on the forward facing spokes under rim braking. However, under disc braking, there should be an additional torque which should increase tension on all spokes where the head leads the nipple and decreased tension on all spokes where the nipple leads the head (I'm sure there's a technical term for it, but it currently escapes my mind). I imagine that these "torsionally derived tensions" in disc applications are greater than the spoke tension changes with rim braking. |
The death of rim brakes?
On Sat, 16 Mar 2019 15:56:04 +0000 (UTC), Ralph Barone
wrote: James wrote: On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. I see. True the spokes see no breaking force but they do see a force simply because they connect the rim to the bicycle and the bicycle (and rider) represent a certain amount of inertia which has to be overcome. No matter what size of disc brake you have, the spoke forces are the same, since the braking force is applied to the hub, which then transfers it through the spokes to the rim/tire. In the limit, the hub is stationary and the wheel is sliding. In this case, the size of the disc determines how much tangential force is applied to the disc, but the force on the spokes is determined by the number of spokes, the lacing pattern and the hub diameter. Exactly. As I said, 36 spokes laced "cross three" :-) -- Cheers, John B. |
The death of rim brakes?
On Sun, 17 Mar 2019 08:30:51 +1100, James
wrote: On 16/3/19 7:38 pm, John B. Slocomb wrote: On Sat, 16 Mar 2019 18:57:21 +1100, James wrote: On 16/3/19 10:32 am, John B. Slocomb wrote: It comes to mind that as the braking resistance is applied at the contact of the tire and the road and that the resistance is applied to the wheel hub that a much stronger disc brake wheel would be required than when using a rim brake as the ratio between the disc brake disc and the contact with the road is approximately 26.5"/7.5" (average 2 sizes of disc rotor) = about 3.5 ratio while a rim brake is only about an inch and a half difference so say 26.5/23.5=1.1 ratio. Based on braking forces it would appear that a disc brake wheel would have to be roughly 3 times stronger than a rim brake wheel. 36 spoke, cross three, wheels anyone? But of course an ATB is already so heavy that the addition of strong wheels is rather a matter of bringing coals to Newcastle. Well, you don't build a disc brake wheel with radial spokes. But they do built a rim brake wheel with radial spokes }-) Yes, I use some I built. It's mostly a fashion thing. The weight reduction by shorter spokes isn't worth worrying about. But as the "weight weenies" say, every little bit helps. Thus the titanium seat bolt clamp bolts :-) In most cases a regular 3x spoke wheel is sufficient to transfer brake forces from the hub to the rim. Imagine the possible force on spokes possible from a 28 tooth chain ring to a 34 tooth rear sprocket? I think that if I were riding around in the mud and mire I probably would want discs but I don't do that. Anywhere that I want to go has paved roads leading to it. I find it rather revealing that in 1880 the League of American Wheelmen, a bicycle advocate group, was formed and one of the first things that they lobbied for was smooth roads. Now that smooth roads, in the U.S. at least, probably make up the majority of the roads people have discovered riding out in the bush where there hardly aren't any roads at all. Where I live there are hundreds of kms of gravel roads that are too rough for my road bike (I've tried). Where as my options are limited by bitumen only roads. Only the main connecting roads are bitumen, and they are high speed roads where drivers dislike passing cyclists safely. I think that people have realised that there are many unmade roads to explore, and there are few cars on them to worry about. -- Cheers, John B. |
The death of rim brakes?
On 3/16/2019 5:50 PM, Ralph Barone wrote:
James wrote: On 17/3/19 2:56 am, Ralph Barone wrote: I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. The spokes may not see any torque between the hub and rim, but are certainly forces due to braking that the spokes see. Now that I think about it some more, yes, there should be increased tension on the rear facing spokes and decreased tension on the forward facing spokes under rim braking. I suspect it would instead be very much like the situation of a bike wheel supporting a vertical load. In that case, there's negligible increase in tension as a reaction to the load. Instead, there's a decrease in tension in the spokes between the hub and the ground. For a wheel with applied vertical load plus rim braking, I think the spokes pointed forward and downward from the hub would see a decrease in tension. The others would see no significant increase. Check out a free body diagram of the wheel, and a FBD of the hub. However, under disc braking, there should be an additional torque which should increase tension on all spokes where the head leads the nipple and decreased tension on all spokes where the nipple leads the head (I'm sure there's a technical term for it, but it currently escapes my mind). I imagine that these "torsionally derived tensions" in disc applications are greater than the spoke tension changes with rim braking. Perhaps- depending on how hard the brakes are applied. I think a lot of folks visualize extreme applications of brakes. But I know almost all my brake applications are very gentle. It just makes no sense to be braking hard very often, and wasting all that energy. I'm pretty sure most people plan ahead enough to minimize their braking. -- - Frank Krygowski |
The death of rim brakes?
On Sat, 16 Mar 2019 23:04:02 -0400, Frank Krygowski
wrote: On 3/16/2019 5:50 PM, Ralph Barone wrote: James wrote: On 17/3/19 2:56 am, Ralph Barone wrote: I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. The spokes may not see any torque between the hub and rim, but are certainly forces due to braking that the spokes see. Now that I think about it some more, yes, there should be increased tension on the rear facing spokes and decreased tension on the forward facing spokes under rim braking. I suspect it would instead be very much like the situation of a bike wheel supporting a vertical load. In that case, there's negligible increase in tension as a reaction to the load. Instead, there's a decrease in tension in the spokes between the hub and the ground. For a wheel with applied vertical load plus rim braking, I think the spokes pointed forward and downward from the hub would see a decrease in tension. The others would see no significant increase. Check out a free body diagram of the wheel, and a FBD of the hub. Certainly true for crossed spokes but what about radial spokes, which are now common in front wheels where, likely, the greatest braking force is imposed? It might be noted that disc brakes impose enough force against the fork to, possibly, cause the axle to move downward in the drop-outs, thus solid axles in some modern bicycles. However, under disc braking, there should be an additional torque which should increase tension on all spokes where the head leads the nipple and decreased tension on all spokes where the nipple leads the head (I'm sure there's a technical term for it, but it currently escapes my mind). I imagine that these "torsionally derived tensions" in disc applications are greater than the spoke tension changes with rim braking. Perhaps- depending on how hard the brakes are applied. I think a lot of folks visualize extreme applications of brakes. But I know almost all my brake applications are very gentle. It just makes no sense to be braking hard very often, and wasting all that energy. I'm pretty sure most people plan ahead enough to minimize their braking. -- Cheers, John B. |
The death of rim brakes?
On Saturday, March 16, 2019 at 11:37:49 PM UTC-4, John B. Slocomb wrote:
On Sat, 16 Mar 2019 23:04:02 -0400, Frank Krygowski wrote: On 3/16/2019 5:50 PM, Ralph Barone wrote: James wrote: On 17/3/19 2:56 am, Ralph Barone wrote: I missed commenting to John earlier. Your visualization of the problem isn't quite right. With rim brakes, the spokes do not see any braking forces, since the brakes sit between the spokes and the tire. The spokes may not see any torque between the hub and rim, but are certainly forces due to braking that the spokes see. Now that I think about it some more, yes, there should be increased tension on the rear facing spokes and decreased tension on the forward facing spokes under rim braking. I suspect it would instead be very much like the situation of a bike wheel supporting a vertical load. In that case, there's negligible increase in tension as a reaction to the load. Instead, there's a decrease in tension in the spokes between the hub and the ground. For a wheel with applied vertical load plus rim braking, I think the spokes pointed forward and downward from the hub would see a decrease in tension. The others would see no significant increase. Check out a free body diagram of the wheel, and a FBD of the hub. Certainly true for crossed spokes but what about radial spokes, which are now common in front wheels where, likely, the greatest braking force is imposed? It might be noted that disc brakes impose enough force against the fork to, possibly, cause the axle to move downward in the drop-outs, thus solid axles in some modern bicycles. However, under disc braking, there should be an additional torque which should increase tension on all spokes where the head leads the nipple and decreased tension on all spokes where the nipple leads the head (I'm sure there's a technical term for it, but it currently escapes my mind). I imagine that these "torsionally derived tensions" in disc applications are greater than the spoke tension changes with rim braking. Perhaps- depending on how hard the brakes are applied. I think a lot of folks visualize extreme applications of brakes. But I know almost all my brake applications are very gentle. It just makes no sense to be braking hard very often, and wasting all that energy. I'm pretty sure most people plan ahead enough to minimize their braking. -- Cheers, John B. Radial Spokes on disc equipped front wheels? Sounds like a recipe for broken spokes. Then again, if the disc brake is concentrating the applied braking force close to the hub perhaps a radial spoke front wheel isn't as prone to spoke breakage as it would be if the braking force was at the rim? I'm thinking about the torque at both locations. It also seems to me that with through axles (iiuc) that a bicyclist LOSES the advantage of a quick release wheel. I know that those damn lawyer lips are a pain in the butt most times and largely negate the reason to have a quick release in the first place. Cheers |
The death of rim brakes?
On 2019-03-15 07:08, wrote:
On Thursday, March 14, 2019 at 6:36:52 PM UTC-7, James wrote: On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. Cable actuated disc callipers are not. Benefit and detriment. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. -- JS I took out the Colnago yesterday since I've been riding the cheaper bikes with all the rain this year. I just put on a set of 25 mm tubeless carbon rims with the Continental GP5000TL tires. Old person with less than 400 miles and very little climbing so far this years means that I'm am slower than frozen snot. But I waited at the top for the group who started 5 minutes after me. They caught me at the top. Rolling down the other side I could COAST faster than the others could pedal. I started as tail end charley because I assumed they would be a fast downhill as up. But I kept overrunning the group and there was one out in front with a new custom steel bike with a new 11 speed Ultegra. I accelerated to catch him and then had to actually put the brakes on to keep from passing him FAST. And then I was 4 bike lengths behind him and coasting most of the rest of the way. When the road flattened out I had to only pedal half the time. As soon as the road went up even a little I was working a whole lot harder than he was. How much do you weigh? I am around 220lbs and that, combined with a steel frame, full tool set and other stuff in the panniers, makes me pass almost everyone else on the downhill. On the uphill, not so much ... Disc and rim brakes don't make a difference in that respect IME. -- Regards, Joerg http://www.analogconsultants.com/ |
The death of rim brakes?
On 2019-03-14 18:36, James wrote:
On 15/3/19 2:17 am, Frank Krygowski wrote: On 3/13/2019 6:32 PM, Joerg wrote: On 2019-03-12 11:13, AMuzi wrote: How many new bicycles have drum brakes? Vanishingly few. This was just meant as an example. Bicycles have largely remained in the stone age, like chuck wagons where a chunk of wood pressed against the steel ring of the wheels to brake. So bicycles kind of skipped a technology. Bikes didn't skip drum brake technology because bikes are primitive. Only a very few bikes adopted drum brakes because that technology wasn't optimum for bikes. It's simplistic at best to pretend what's best for one application is best for all applications. Every design choice comes with benefits and detriments, and those are not the same for a 4000 pound car as for a 20 pound bike. Bicycle rim brakes have worked fine for over 99.999% users for the past 100+ years. When mountain bikes came into fashion, some off-roaders found a different set of benefits vs. detriments, and discs made sense for them. But then fashion and marketing took over, pushing discs toward road bikes. Yes, we'll get a few testimonials here claiming discs are "better." We get very few details on benefits vs. detriments. For a while, the trend for road bikes was very narrow tyres pumped up to very high pressure. 18 mm of tyre is pretty skinny. Gradually the tyre width had become standard at 23 mm for road bikes. Now there is an emerging trend to ride wider tyres, with some claiming much wider tyres are not only as fast but faster! I suspect there is a diminishing return with wind resistance. I think the common sweet spot concensus is 25mm which is what I am riding right now. Though I'd rather have 32mm in back for CX capability but unfortunately the frame isn't built for that. Now I use a 25 mm rear tyre (that measures 27 mm), and to remove the wheel I must release the brake lever (Campagnolo) or deflate the tyre. With a 23 mm tyre I don't need to do that. With a disc brake I don't need to fiddle with the brakes regardless of tyre width. That's a benefit. That I don't understand. Even the early 80's Shimano 600 set on my road bike has little release handles on each caliper to get out a 25mm+ wheel with lots of room to spare. In fact sometimes when you go to shove a wheel in with rim brakes and centre or dual pivot callipers, you can catch the calliper and move it from centred. Then you have to fix that or have rubbing brakes. That doesn't happen with discs. Though a disc does get bent easily and you have to pay more attention when re-installing a wheel. Fixing is easy as well as long as you do not touch the disc with bare hands. It is possible with hydraulic disc callipers to squeeze the brake lever while the wheel is out, and then have trouble moving the pads apart again to insert the wheel. This falls under the category "Don't do that!" :-) ... That's a detriment, but doesn't affect cable actuated disc brake callipers. Hydraulic disc callipers are self adjusting like car hydraulic disc callipers. ... Ahm, sort of. The reservoirs are typically a bit small to accommodate all the wear. I have to top off with DOT-4 at times which is nasty stuff when it gets onto clothes and things. Cable actuated disc callipers are not. Benefit and detriment. Cable calipers are very easy to adjust, just turn a knurled trim knob. A downside of many is that they only have one moving piston while the opposite piston is fixed. The rotor flexes to the side every time you brake. Beats me why they design them that way. Hydraulic disc systems sometimes need bleeding. This requires either a visit to a shop or a bit more kit ($30 - $50) for the home maintenance person. Detriment. Probably not good if you are out on a tour. IME it's needed once a year at the most. But when it's needed it really is and not doing it can result in a bad crash. ... Cables are probably more reliable. Cable operated discs work fine, and there are also cable/hydraulic systems, where the calliper is hydraulic and self adjusting, and actuated via a cable. The cable discs I used just don't have the same kind of stopping power with modest lever force as hydraulic disc brakes. Disc brake modulation is generally better. That is you can hold the point of not quite skidding more easily. Benefit. I can't confirm that one. My road bike with rim brakes is just as good in modulating stopping power as my MTB with hydraulic disc brakes. UNLESS ... it rains a lot. Then it has zero stopping power for a sometimes gut-churning 1-2sec. Disc brakes tend to work better in wet weather, or IOW, work the same regardless of wet weather. Rim brakes rarely work as well when the rims are wet. Rim brakes on carbon fibre rims has never been a happy marriage, but with disc brakes that problem is eliminated. Thus aerodynamic, strong, stiff, light weight rims are now easier to manufacture and use - made of carbon fibre. Rim brakes do erode rims. Disc brakes do not. I guess the disc rotor will wear out, but I'd rather replace a rotor than a rim. Plus it's a whole lot cheaper and the replacement job takes a couple of minutes versus the better part of a Saturday morning. It seems to me that many people try disc brakes and find few drawbacks. That's just my opinion, unsubstantiated by statistics. I was sold on disc brakes after about five seconds of use. When I almost flew over the handlebar of my new MTB during a test ride in the LBS parking lot, despite having pulled the handle with just two fingers. The rear of the MTB actually bucked upwards. It felt like having power-assist brakes. Woohoo! Are rim brakes good enough? Sure! They have been for a long time. Are disc brakes better? Yes I think so. Not outstandingly, but better. I'm not about to have my road bike modified to take disc brakes, and I wouldn't let the choice of brakes on a new bike dictate what I bought. YMMV. I do. Should I ever need a new road bike it will have discs or I won't buy. -- Regards, Joerg http://www.analogconsultants.com/ |
The death of rim brakes?
On Monday, March 18, 2019 at 3:32:49 PM UTC-4, Joerg wrote:
Snipped I was sold on disc brakes after about five seconds of use. When I almost flew over the handlebar of my new MTB during a test ride in the LBS parking lot, despite having pulled the handle with just two fingers. The rear of the MTB actually bucked upwards. It felt like having power-assist brakes. Woohoo! Snipped I do. Should I ever need a new road bike it will have discs or I won't buy. -- Regards, Joerg http://www.analogconsultants.com/ Back around 1982 I bought a Velo Sport Columbus SL Dura Ace AX equipped bicycle and on the ride home was getting squeezed into parked cars by a streetcar because the road was narrowing quite a bit. I hit the brakes and the rear wheel lifted quite a bit before I released the front brake lever and hit the brakes again. That was with the AX caliper brake. I've always loved the braking of those brakes. Cheers |
The death of rim brakes?
On 2019-03-18 13:57, Sir Ridesalot wrote:
On Monday, March 18, 2019 at 3:32:49 PM UTC-4, Joerg wrote: Snipped I was sold on disc brakes after about five seconds of use. When I almost flew over the handlebar of my new MTB during a test ride in the LBS parking lot, despite having pulled the handle with just two fingers. The rear of the MTB actually bucked upwards. It felt like having power-assist brakes. Woohoo! Snipped I do. Should I ever need a new road bike it will have discs or I won't buy. -- Regards, Joerg http://www.analogconsultants.com/ Back around 1982 I bought a Velo Sport Columbus SL Dura Ace AX equipped bicycle and on the ride home was getting squeezed into parked cars by a streetcar because the road was narrowing quite a bit. I hit the brakes and the rear wheel lifted quite a bit before I released the front brake lever and hit the brakes again. That was with the AX caliper brake. I've always loved the braking of those brakes. Now try the same on a rainy day. Yeah, a rim brake can still lift the rear but it could be 1-2sec too late. I don't want that. -- Regards, Joerg http://www.analogconsultants.com/ |
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