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#271
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Stronger rubber cement?
On Friday, January 20, 2017 at 6:38:47 PM UTC-5, John B. wrote:
On Fri, 20 Jan 2017 07:43:20 -0800, Joerg wrote: On 2017-01-19 19:00, John B. wrote: On Thu, 19 Jan 2017 14:57:42 -0800, Joerg wrote: On 2017-01-19 14:39, Doug Landau wrote: On road bikes it usually happens when hitting a rock "just so". Like when the rock gets under the tire off center and flies off to the side with gusto. Haha and makes a loud CRACK as it hits the passenger door or window of the car to your left :-) No kidding, that has happend. Also, drivers give me extra wide margin when I just came off a dirt path in bad weather and all sorts of gunk flies off my rear wheel. I am beginning to wonder. You have repeatedly stated that your usual speed is 20 MPH. Now, a 26 x 3.0 tire will be spinning at about 250 RPM at that speed..... But this speeding tire accumulates "all kind of gunk"? As explained many times 20mph is the speed on flat sections of trail or slightly higher when downsloping a little. My average trail speed is more around 10-12mph depending on turf unless I want to push it. Meaning there are murky or gnarly stretches in the low single digit mph. There are people on this NG who do not understand the difference between top speed and average speed. On such trails I often slow down to enjoy the scenery, animals, and so on. Something that the "bicycles belong on road" people will likely never understand. Then I ride on 29" wheels. A usual scenario is that I come back on singletrack from Placerville and the last section before entering a regular road is this: http://www.analogconsultants.com/ng/bike/Chapparal2.jpg Imagine that after three days of rain. Also, on rainy days my average speed on the "real" trail can drop substantially because the rear wheel becomes stuck several times. Big clump of mud caked up near the BB, wheel will hardly turn even in granny gear, have to stop, look around for a sturdy branch piece of manzanita, poke the mud out of there, continue the ride. Until it gets stuck again a few miles later. Sometimes it's so bad that I strap that piece of manzanita onto the rack. I ask as my road bike, who's wheels are spinning at only about 157 RPM don't seem to accumulate any junk at all. Well, do your road bike tires have knobbies? BTW, my road bike does fling dirt off the wheels after a muddy stretch of "bush road" and I have caked up its BB area with mud. Usually purposely rolling through some water puddles washes the mud off the tires, something that does not work for the MTB tires. You are almost unbelievable. You have a double handful of mud lodged on the bottom bracket and you need to run about and find a stick to dislodge it. Why can't you just grab a handful and throw it on the ground... oh, of course you'd get your fingers dirty, wouldn't you. Is "effete a word you understand? -- Cheers, John B. Perhaps Joerg doesn't but he does know Troll and he's an expert on trolling as nearly evey thread he starts shows. I think that at least 90% of his posts are pure unadulterated El Toro Poo Poo. Cheers |
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#272
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Stronger rubber cement?
On Fri, 20 Jan 2017 10:17:56 -0800, Joerg
wrote: On 2017-01-20 09:35, Frank Krygowski wrote: On 1/20/2017 10:43 AM, Joerg wrote: As explained many times 20mph is the speed on flat sections of trail or slightly higher when downsloping a little. My average trail speed is more around 10-12mph depending on turf unless I want to push it. Meaning there are murky or gnarly stretches in the low single digit mph. There are people on this NG who do not understand the difference between top speed and average speed. Well, to be fair, you've bragged endlessly about how fast you ride when that suits you, and you've switched to saying how slow you ride when that suits you. You seldom clarified whether you were talking about average or instantaneous speed, until people began calling you on the discrepancies in your posts. No. All I wrote was that I routinely ride 20mph on trails and that's a fact. There are no discrepancies. Back then I brought that up because I expect the riding equipment to hold up under those conditions and some doesn't. As I remember it I questioned you some time ago about your statement "usually ride at 20 mph" and at that time you answered that was downhill. Now you say "routinely" without the "downhill". Given that the usual sped of professional MTB racers is in the 18 mph range for average courses and in fact one site discussing professional racers states that, " An impressive pace for a pro mountain biker, on average, could be around 15 mph, or a 4-minute mile." I think that you should change your name from Joerg" to "Übermensch". And yes, I do take the liberty of riding 1mph at times when I want to. On singletrack watching animals or scenery. Or recently on a MUP to watch the massive release of water at Folsom Lake dam. For me bicycling is about freedom and that also means freedom from motor vehicle traffic whenever possible. Whether I ride at 20mph or 1mph nobody gets bothered by it. -- Cheers, John B. |
#273
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Stronger rubber cement?
On Fri, 20 Jan 2017 18:12:21 -0500, Frank Krygowski
wrote: On 1/20/2017 3:43 PM, jbeattie wrote: I have hydraulic discs on a Roubaix and cable discs on my CX commuter bike. I've never gone OTB because of my brakes. The last time I went OTB it was with ordinary caliper brakes and because my son had crashed in front of me on a wet descent. The hydraulic brakes are powerful and they do take some use to understand. Front braking is not all that much different from a good dual pivot; however, rear braking is much more positive, and that is where you have to avoid ham-handedness. This takes about 90 seconds to figure out, and most rear wheel skids are controllable during the learning period. I think I might have problems if I had two similar bikes, one with caliper brakes and one with hydraulic discs - especially if the disc bike wasn't ridden as frequently. My riding style doesn't involve much emergency braking - or really, much speed control on downhills. I like the fast coasting. I think that if an emergency braking event occurred on a disc bike, I might overreact. The scariest braking event I can recall happened about 1.5 years ago, IIRC. It was a club ride through our large, somewhat hilly metropark, and on one long 30+ mph downhill, I coasted off the front as usual. Suddenly two fawns appeared from the woods and one trotted out in front of me. I had never braked that hard and suddenly from such a high speed, and I felt like I was on the edge of control. That's with well set up cantilevers that I'm very, very used to. I suspect with discs, I'd have gone down. Both the cable and hydraulic brakes beat the hell out of calipers in rain and slop, like the snow slop I've been trying to ride in. In dry weather, any good rim brake will do the job. I don't see any reason for hydraulic discs on high-end race bikes that will never be ridden in the rain, except maybe to avoid over-heating CF rims -- which could be a real problem with tubulars, although I'm just speculating. Personally, I think its just marketing. No argument there. I'm lucky to be able to avoid riding in those conditions. Somehow I suspect that ultimate bicycle stopping ability is less dependent on types of brakes and far more dependent on tire-pavement friction coefficient. -- Cheers, John B. |
#274
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Stronger rubber cement?
On 2017-01-20 15:38, John B. wrote:
On Fri, 20 Jan 2017 07:43:20 -0800, Joerg wrote: On 2017-01-19 19:00, John B. wrote: On Thu, 19 Jan 2017 14:57:42 -0800, Joerg wrote: On 2017-01-19 14:39, Doug Landau wrote: On road bikes it usually happens when hitting a rock "just so". Like when the rock gets under the tire off center and flies off to the side with gusto. Haha and makes a loud CRACK as it hits the passenger door or window of the car to your left :-) No kidding, that has happend. Also, drivers give me extra wide margin when I just came off a dirt path in bad weather and all sorts of gunk flies off my rear wheel. I am beginning to wonder. You have repeatedly stated that your usual speed is 20 MPH. Now, a 26 x 3.0 tire will be spinning at about 250 RPM at that speed..... But this speeding tire accumulates "all kind of gunk"? As explained many times 20mph is the speed on flat sections of trail or slightly higher when downsloping a little. My average trail speed is more around 10-12mph depending on turf unless I want to push it. Meaning there are murky or gnarly stretches in the low single digit mph. There are people on this NG who do not understand the difference between top speed and average speed. On such trails I often slow down to enjoy the scenery, animals, and so on. Something that the "bicycles belong on road" people will likely never understand. Then I ride on 29" wheels. A usual scenario is that I come back on singletrack from Placerville and the last section before entering a regular road is this: http://www.analogconsultants.com/ng/bike/Chapparal2.jpg Imagine that after three days of rain. Also, on rainy days my average speed on the "real" trail can drop substantially because the rear wheel becomes stuck several times. Big clump of mud caked up near the BB, wheel will hardly turn even in granny gear, have to stop, look around for a sturdy branch piece of manzanita, poke the mud out of there, continue the ride. Until it gets stuck again a few miles later. Sometimes it's so bad that I strap that piece of manzanita onto the rack. I ask as my road bike, who's wheels are spinning at only about 157 RPM don't seem to accumulate any junk at all. Well, do your road bike tires have knobbies? BTW, my road bike does fling dirt off the wheels after a muddy stretch of "bush road" and I have caked up its BB area with mud. Usually purposely rolling through some water puddles washes the mud off the tires, something that does not work for the MTB tires. You are almost unbelievable. You have a double handful of mud lodged on the bottom bracket and you need to run about and find a stick to dislodge it. Why can't you just grab a handful and throw it on the ground... oh, of course you'd get your fingers dirty, wouldn't you. Can you possibly imagine that there are occasions where one wants to arrive at a destination without dirty hands? Even when ... gasp ... using a bicycle for transportation in ... oh horror! ... non-ideal weather along less than stellar paths? Is "effete a word you understand? Is "utility cycling" an expression you understand? -- Regards, Joerg http://www.analogconsultants.com/ |
#275
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Stronger rubber cement?
On Friday, January 20, 2017 at 3:38:47 PM UTC-8, John B. wrote:
On Fri, 20 Jan 2017 07:43:20 -0800, Joerg wrote: On 2017-01-19 19:00, John B. wrote: On Thu, 19 Jan 2017 14:57:42 -0800, Joerg wrote: On 2017-01-19 14:39, Doug Landau wrote: On road bikes it usually happens when hitting a rock "just so". Like when the rock gets under the tire off center and flies off to the side with gusto. Haha and makes a loud CRACK as it hits the passenger door or window of the car to your left :-) No kidding, that has happend. Also, drivers give me extra wide margin when I just came off a dirt path in bad weather and all sorts of gunk flies off my rear wheel. I am beginning to wonder. You have repeatedly stated that your usual speed is 20 MPH. Now, a 26 x 3.0 tire will be spinning at about 250 RPM at that speed..... But this speeding tire accumulates "all kind of gunk"? As explained many times 20mph is the speed on flat sections of trail or slightly higher when downsloping a little. My average trail speed is more around 10-12mph depending on turf unless I want to push it. Meaning there are murky or gnarly stretches in the low single digit mph. There are people on this NG who do not understand the difference between top speed and average speed. On such trails I often slow down to enjoy the scenery, animals, and so on. Something that the "bicycles belong on road" people will likely never understand. Then I ride on 29" wheels. A usual scenario is that I come back on singletrack from Placerville and the last section before entering a regular road is this: http://www.analogconsultants.com/ng/bike/Chapparal2.jpg Imagine that after three days of rain. Also, on rainy days my average speed on the "real" trail can drop substantially because the rear wheel becomes stuck several times. Big clump of mud caked up near the BB, wheel will hardly turn even in granny gear, have to stop, look around for a sturdy branch piece of manzanita, poke the mud out of there, continue the ride. Until it gets stuck again a few miles later. Sometimes it's so bad that I strap that piece of manzanita onto the rack. I ask as my road bike, who's wheels are spinning at only about 157 RPM don't seem to accumulate any junk at all. Well, do your road bike tires have knobbies? BTW, my road bike does fling dirt off the wheels after a muddy stretch of "bush road" and I have caked up its BB area with mud. Usually purposely rolling through some water puddles washes the mud off the tires, something that does not work for the MTB tires. You are almost unbelievable. You have a double handful of mud lodged on the bottom bracket and you need to run about and find a stick to dislodge it. Why can't you just grab a handful and throw it on the ground... oh, of course you'd get your fingers dirty, wouldn't you. Is "effete a word you understand? Great example :-) |
#276
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Stronger rubber cement?
On Friday, January 20, 2017 at 3:18:13 PM UTC-8, AMuzi wrote:
On 1/20/2017 5:12 PM, Frank Krygowski wrote: On 1/20/2017 3:43 PM, jbeattie wrote: -snip- I think I might have problems if I had two similar bikes, one with caliper brakes and one with hydraulic discs - especially if the disc bike wasn't ridden as frequently. -snip- Agreed. See also front-engine front drive drivers vs. rear engine rear drive drivers. Most of the time it doesn't matter. When it does matter, a quick reaction in the other car will get you killed. I don't have any problem switching between my hydraulic discs and caliper brakes. My problem is switching between STI and SRAM double tap. I miss more shifts than I make on the double tap, at least early in any ride. -- Jay Beattie. |
#277
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Stronger rubber cement?
On 2017-01-20 15:53, John B. wrote:
On Fri, 20 Jan 2017 10:17:56 -0800, Joerg wrote: On 2017-01-20 09:35, Frank Krygowski wrote: On 1/20/2017 10:43 AM, Joerg wrote: As explained many times 20mph is the speed on flat sections of trail or slightly higher when downsloping a little. My average trail speed is more around 10-12mph depending on turf unless I want to push it. Meaning there are murky or gnarly stretches in the low single digit mph. There are people on this NG who do not understand the difference between top speed and average speed. Well, to be fair, you've bragged endlessly about how fast you ride when that suits you, and you've switched to saying how slow you ride when that suits you. You seldom clarified whether you were talking about average or instantaneous speed, until people began calling you on the discrepancies in your posts. No. All I wrote was that I routinely ride 20mph on trails and that's a fact. There are no discrepancies. Back then I brought that up because I expect the riding equipment to hold up under those conditions and some doesn't. As I remember it I questioned you some time ago about your statement "usually ride at 20 mph" and at that time you answered that was downhill. Now you say "routinely" without the "downhill". And that is what I always said. ... Given that the usual sped of professional MTB racers is in the 18 mph range for average courses and in fact one site discussing professional racers states that, " An impressive pace for a pro mountain biker, on average, could be around 15 mph, or a 4-minute mile." ^^^^^^^^ Do you, like some here, not understand the difference between average speed and top speed? Nobody can hold 20mph on a MTB for three hours but it is easy to do that on a flat section for a limited time. It is by nature limited because the terrain on other sections would make 20mph almost a suicide ride. My point back then was not to brag about me being a super action hero because I am not. The point was that I believe MTBs must be capable of sustaining regular 20mph episodes on a raggedy trail where everything rattles. I think that you should change your name from Joerg" to "Übermensch". I am an average cyclist doing rides of 20-50 miles at a time. There are plenty of people that would beat me on average speed, for example the bike shop owner where I bought my recent MTB. He is a competion rider and a bit younger. [...] -- Regards, Joerg http://www.analogconsultants.com/ |
#278
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Stronger rubber cement?
On Friday, January 20, 2017 at 4:00:15 PM UTC-8, John B. wrote:
On Fri, 20 Jan 2017 18:12:21 -0500, Frank Krygowski wrote: On 1/20/2017 3:43 PM, jbeattie wrote: I have hydraulic discs on a Roubaix and cable discs on my CX commuter bike. I've never gone OTB because of my brakes. The last time I went OTB it was with ordinary caliper brakes and because my son had crashed in front of me on a wet descent. The hydraulic brakes are powerful and they do take some use to understand. Front braking is not all that much different from a good dual pivot; however, rear braking is much more positive, and that is where you have to avoid ham-handedness. This takes about 90 seconds to figure out, and most rear wheel skids are controllable during the learning period. I think I might have problems if I had two similar bikes, one with caliper brakes and one with hydraulic discs - especially if the disc bike wasn't ridden as frequently. My riding style doesn't involve much emergency braking - or really, much speed control on downhills. I like the fast coasting. I think that if an emergency braking event occurred on a disc bike, I might overreact. The scariest braking event I can recall happened about 1.5 years ago, IIRC. It was a club ride through our large, somewhat hilly metropark, and on one long 30+ mph downhill, I coasted off the front as usual. Suddenly two fawns appeared from the woods and one trotted out in front of me. I had never braked that hard and suddenly from such a high speed, and I felt like I was on the edge of control. That's with well set up cantilevers that I'm very, very used to. I suspect with discs, I'd have gone down. Both the cable and hydraulic brakes beat the hell out of calipers in rain and slop, like the snow slop I've been trying to ride in. In dry weather, any good rim brake will do the job. I don't see any reason for hydraulic discs on high-end race bikes that will never be ridden in the rain, except maybe to avoid over-heating CF rims -- which could be a real problem with tubulars, although I'm just speculating. Personally, I think its just marketing. No argument there. I'm lucky to be able to avoid riding in those conditions. Somehow I suspect that ultimate bicycle stopping ability is less dependent on types of brakes and far more dependent on tire-pavement friction coefficient. Yes, but there are times when you can't stop when the brakes are wet but you still have decent traction. There is that free-fall period after you squeeze a caliper/rim brake when riding in heavy rain, and it feels like you're going faster and not slower. The brake finally squeegees off the rim, and you get stopping, but there is that moment of terror. You get some of that even with a disc, but it is very brief. Now, if you just slammed on some hydraulic disc brakes on wet pavement, you would probably go sliding, and good brakes or not, I don't lay the bike into wet turns. I also pick my tread compound. Tire selection can make a big difference -- more so back in the Umma Gumma and clay-based pigment tire days (the first generation colored tires were like riding on banana peels in the rain), but some tires are still better than others. -- Jay Beattie. |
#279
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Stronger rubber cement?
On Friday, January 20, 2017 at 2:56:51 PM UTC-8, Joerg wrote:
On 2017-01-20 14:33, jbeattie wrote: On Friday, January 20, 2017 at 1:56:19 PM UTC-8, Joerg wrote: On 2017-01-20 13:16, wrote: On Friday, January 20, 2017 at 12:58:02 PM UTC-8, Joerg wrote: On 2017-01-20 11:31, wrote: On Thursday, January 19, 2017 at 12:28:02 PM UTC-8, Joerg wrote: On 2017-01-18 12:53, wrote: [...] My MTB has very fast reacting disc brakes. I generally ride with just the index and middle fingers over the brake handles. A good squeeze from two fingers can lock up the wheels. Yet I only locked them up when I wanted to. Like when I accidentally blew by a trail turn-off and was heading for a rock slide, and let the front and rear dig into the loose gravel. Beattie tells us that he can lock up rim brakes with road brakes. I wonder how steep your descents are. Not sure what that has to do with brake handle force. We have singletrack sections where you can only slow down if you additionally set a foot down or the bike will slowly pick up speed no matter what. I now walk some of those after a friend had a spectacular crash on one. Rim brakes do not work well in mud and rain. The worst is the delay when the rim is soaked. Precious seconds go by and that could cause a crash. Almost has on my old MTB with rim brakes. Whenever I go through mud or water crossings I ride a little way with the brakes dragging to clear them. I've never had any problem with the rim brakes in those conditions. My comeuppance happened on the old MTB. A puddle had formed before a sharp turn, no big deal. I thought. Until I reached in to brake and ... nada, zip ... "Oh s..t!". I had ridden that stretch before with a Specialized Endoro from a friend and due to disc brakes never noticed how bad this situation would be with rim brakes. During summer I never noticed it even on the rim-brake MTB because then rim brakes work. I also clear the brakes after puddles. When they were muddy puddles this results in an awful grinding noise and you can hear some of the rim surface being eaten up. The rims on my old MTB had deep grooves after only 1000mi of use. They'd never make it to 10000mi. Discs are well-suited for MTBs which are ridden in dirt (wet and dry) and see very steep descents with grades well beyond any paved road. Can't argue with discs on MTBs. They are also well-suited for winter riding in rainy climates like the PNW. I don't think they are needed for the occasional ride through a puddle on a racing bike. Tom can squeegee his rim in a revolution, and he doesn't have to worry much about grit turning his caliper brakes into lathes. When I used rim brakes on my commuter, I was wearing through rims. My current disc rims are pristine, and rotors last a long, long time. I live in Norcal and it all depends on your routes. The regular commuters down in the valley will be fine with rim brakes. But not us "non-flatlanders". Every time I head down towards the valley I have to cross a dirt path at least once. Even offroad vehicles have become stuck there. No problem in the summer but this time of year the rim brakes make a horrid grinding noise unless I find a clean enough puddle to rinse the rims. Well, the problem I had with the disks on a full suspension were that the disks were steel and the brake pads would last a month in wet weather. Certainly cheaper than rims but the disks would also get all grooved up and then they would need replacing quite rapidly. Hydraulic discs have a nice feel and are very positive. I like them, but I could live with a good cable disk, although my rear BB5 is pretty limp -- and I'm not clear why. That is something I need to work on more. Anyway, a decent cable disc is a good choice for a wet-weather commuter/training bike. I have hydraulics on the MTB. Before that I test-rode a MTB with cable disc brakes and came away non-plussed. It's got to be hydraulics if possible. Unfortuantely most disc road bikes have cables. I'd accept cables on a road bike but never on MTB. Riding a CX off-road is so much more fun that an anchor MTB that I'm willing to put up with either problem. |
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