#11
|
|||
|
|||
MTB randonneur
On Sun, 03 Jun 2018 20:06:31 +0200, Emanuel Berg
wrote: Jeff Liebermann wrote: How wide a tire do you need? I don't need especially wide tires. Just not 32 and preferably wider than 35. Shooting from the holster, I'd say my prefered tire size is 622-40, 622-42, or 622-47. Methinks they are the same as 28x1.50, 28x1.60, and 28x1.75. Looking at Schwalbe touring tires, they're available in those sizes in a variety of tread patterns. https://www.schwalbetires.com/bike_tires/road_tires Perhaps custom rims might be a solution. Something like this: http://www.spontaneousfire.com/trikeofdeath.htm For normal riding, you only install one tire on the extra wide rim. For heavy loads or touring, you install two tires. This arrangement might also provide useful redundancy in the event you get a flat tire. I think 3 side by side tires might be better than two. Soon, everyone will be riding on extra wide rims and multiple tires. But this is me just projecting the project based on my general experience and what I've read. I never did any randonneuring whatsoever on any bike! Neither have I, and it shows. However, I have done some touring and bicycle camping in the distant past. Prior to these adventures, I did read some books and magazine articles on touring. I then ignored most of the advice and did what I thought best, with predictable results. Incidentally, I also used my touring bicycle to do local service calls in my computer repair business. At the time, computers were still too big and heavy to be effectively transported on a bicycle. I also had to carry several filing boxes full of floppy disks and a mess of tools. Leaving anything on a parked bicycle was a security problem. I might try it again as the computers are much smaller today and all the software I need are now on about five USB flash drives. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Ads |
#12
|
|||
|
|||
MTB randonneur
Jeff Liebermann wrote:
I don't need especially wide tires. Just not 32 and preferably wider than 35. Shooting from the holster, I'd say my prefered tire size is 622-40, 622-42, or 622-47. Methinks they are the same as 28x1.50, 28x1.60, and 28x1.75. I think you are right: 47-622 28 x 1.75 x 2 47-622 28 x 1-5/8 x 1-3/4 700x45C 28x1.75 47-622 27 x 1.75 700x45C 42-622 28 x 1-5/8 700x40C 40-622 28 x 1-5/8 x 1-1/2 700x38C These digits BTW are simply what I have found on tires so there is no attempt at normalizing the English sizes. It seems sometimes they say 1-3/4 and sometimes 1.75. I also have these: 37-622 28 x 15/8 x 13/8 700x35C 32-622 28 x 14/8 x 10/8 Perhaps just lack of standardization/normalization behind those "more than 8 eights" fractions...? Some of the decimals seem to be unexpressable (cleanly) as eights or sixteenths tho? -- underground experts united http://user.it.uu.se/~embe8573 |
#13
|
|||
|
|||
MTB randonneur
Perhaps just lack of
standardization/normalization behind those "more than 8 eights" fractions...? Some of the decimals seem to be unexpressable (cleanly) as eights or sixteenths tho? Is this [1] the correct algorithm? It translates 1.75 into 1-3/4 at least :P ths () { local value=$1 local denom=${2:-16} local whole=$(( int(floor($value)) )) local rest=$(( $value - $whole )) local frac=$(( int(rint($rest * $denom)) )) if (( $(( $frac % 2 )) == 0 )); then local new_denom=$(( denom / 2 )) ths $value $new_denom else echo $whole-${frac}/${denom} fi } # $ ths 1.75 # 1-3/4 [1] http://user.it.uu.se/~embe8573/conf/.zsh/math -- underground experts united http://user.it.uu.se/~embe8573 |
#14
|
|||
|
|||
MTB randonneur
On Tue, 05 Jun 2018 00:08:22 +0200, Emanuel Berg
wrote: Perhaps just lack of standardization/normalization behind those "more than 8 eights" fractions...? Some of the decimals seem to be unexpressable (cleanly) as eights or sixteenths tho? Is this [1] the correct algorithm? It translates 1.75 into 1-3/4 at least :P Wrong. A 26x1.5 tire and a 26x1-1/2 tire are different tire sizing systems: http://www.sheldonbrown.com/tire-sizing.html See charts of fractional and decimal sizes. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#15
|
|||
|
|||
MTB randonneur
Jeff Liebermann wrote:
A 26x1.5 tire and a 26x1-1/2 tire are different tire sizing systems: http://www.sheldonbrown.com/tire-sizing.html See charts of fractional and decimal sizes. It says this [1], but doesn't explain how the systems work what I can see. If you compare one 2x1.5 and a 26x1-1/2, why are they not interchangeable, and what tire is wider? In my experience the width is less important than the diameter. One can make it work with different widths. But perhaps that is different in the road bike and MTB worlds? BTW is this also a "different tire sizing system" 37-622 28 x 15/8 x 13/8 700x35C 32-622 28 x 14/8 x 10/8 ? [1] Does Point Seven Five Equal Three Quarters? Inch-based designations sometimes express the width in a decimal (26 x 1.75) and sometimes as a common fraction (26 x 1 3/4). This is the most common cause of mismatches. Although these size designations are mathematically equal, they refer to different size tires, which are NOT interchangeable. It is dangerous to generalize when talking about tire sizing, but I would confidently state the following: Brown's Law Of Tire Sizing: If two tires are marked with sizes that are mathematically equal, but one is expressed as a decimal and the other as a fraction, these two tires will not be interchangeable. -- underground experts united http://user.it.uu.se/~embe8573 |
#16
|
|||
|
|||
MTB randonneur
On Tue, 05 Jun 2018 14:01:19 +0200, Emanuel Berg
wrote: Jeff Liebermann wrote: A 26x1.5 tire and a 26x1-1/2 tire are different tire sizing systems: http://www.sheldonbrown.com/tire-sizing.html See charts of fractional and decimal sizes. It says this [1], but doesn't explain how the systems work what I can see. For those who believe, no explanation is necessary. For those who do not believe, no explanation is possible. Brown's Law Of Tire Sizing: If two tires are marked with sizes that are mathematically equal, but one is expressed as a decimal and the other as a fraction, these two tires will not be interchangeable. So the prophet has written, so it must be. Google a little for some history on the topic. You'll get a wide variety of explanations and conspiracy theories. https://www.google.com/search?q=history+of+bicycle+tire+sizes For example: The History of Mountain Bike Wheel Size (Gary Fisher) https://www.youtube.com/watch?v=8syt59gK65o (4:07) https://mariposabicycles.ca/blog/2015/01/26/tire-and-rim-sizes/ "Since the article was written, 650B wheels and tires have become popular and more easily available. But to confuse matters, they are now being called 27.5’s which makes no sense as they are far smaller than 27? wheels. And, 29’ers are in fact 700c wheels with larger section tires, adding a little more confusion to an already nonsensical subject." To insure maximum confusion, 1 inch = 25 mm. A guide to tyre sizes. http://www.users.globalnet.co.uk/~pattle/ddgcs/tyres.htm I'm not sure if they use Pi = 3.14159 or 3.0 in the calculations. In my never humble opinion, you can't specify bicycle tires with just two numbers. See how automobile tires are specified for an example of how it could and should be done. If that means yet another numbering system, so be it. https://tiresize.com/conversion-chart/ -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#17
|
|||
|
|||
MTB randonneur
Emanuel Berg wrote:
:Jeff Liebermann wrote: : A 26x1.5 tire and a 26x1-1/2 tire are : different tire sizing systems: : http://www.sheldonbrown.com/tire-sizing.html : See charts of fractional and decimal sizes. :It says this [1], but doesn't explain how the :systems work what I can see. If you compare one What "System"? They're tire sizes. They were invented by some manufacturer, who thought there was a market, at different times and different places. 26x 1 3/4 is the same as 650C, which was commonly used on triathalon bikes. 26 x 1.75 is a US size that was used for beach cruisers with wide tires; those bikes became the first mountain bikes, whcih is why 26" ruled the mountain bike world until someone thought we needed 29ers and 27.5 ers. :2x1.5 and a 26x1-1/2, why are they not :interchangeable, and what tire is wider? 2xdecimal are 571 mm diameter, 25X1 1/2 is 559. Unless I have that backwards, which I probably do. Then it's the other way around. Either way, it's clear why tires are not interchangable. Bike tire widths are all a fantasy, so who knows which is wider. -- sig 72 |
#18
|
|||
|
|||
MTB randonneur
David Scheidt wrote:
2x1.5 and a 26x1-1/2, why are they not interchangeable, and what tire is wider? 2xdecimal are 571 mm diameter, 25X1 1/2 is 559. Unless I have that backwards, which I probably do. Then it's the other way around. Either way, it's clear why tires are not interchangable. Bike tire widths are all a fantasy, so who knows which is wider. 26xdecimal is 571 and 26x1-1/2 is 559? But I have 26x1-1/2 that are 584. I also have 26xdecimal that are 559! Or did you really mean 25? 44-584 26 x 1-5/8 x 1-1/2 40-584 26 x 1-1/2 650x35B [...] 56-559 26 x 2.10 559 26 x 2 MTB and derivatives 26 x 2 trailer, 2 - 19-3/4 50-559 26 x 2.0 50-559 26 x 1.95 But OK, it *is* the diameter that is different after all! And you know this by examining not the digits but the notational styles of the tire width indication? Wow, it makes sense even to me! -- underground experts united http://user.it.uu.se/~embe8573 |
#19
|
|||
|
|||
MTB randonneur
On Tuesday, June 5, 2018 at 8:11:10 AM UTC-7, David Scheidt wrote:
Emanuel Berg wrote: :Jeff Liebermann wrote: : A 26x1.5 tire and a 26x1-1/2 tire are : different tire sizing systems: : http://www.sheldonbrown.com/tire-sizing.html : See charts of fractional and decimal sizes. :It says this [1], but doesn't explain how the :systems work what I can see. If you compare one What "System"? They're tire sizes. They were invented by some manufacturer, who thought there was a market, at different times and different places. 26x 1 3/4 is the same as 650C, which was commonly used on triathalon bikes. 26 x 1.75 is a US size that was used for beach cruisers with wide tires; those bikes became the first mountain bikes, whcih is why 26" ruled the mountain bike world until someone thought we needed 29ers and 27.5 ers. :2x1.5 and a 26x1-1/2, why are they not :interchangeable, and what tire is wider? 2xdecimal are 571 mm diameter, 25X1 1/2 is 559. Unless I have that backwards, which I probably do. Then it's the other way around. Either way, it's clear why tires are not interchangable. Bike tire widths are all a fantasy, so who knows which is wider. Why is an inch an inch? Why isn't it like an inch and a quarter -- or a quarter inch. They did that with millimeters. Have you seen how small those are? I bet that some guy came up with a millimeter and showed it to his boss who said, "no, too big . . . make it smaller." It's the same deal with tires. Did I mention mountain lions? Why do they have three names -- cougars, pumas and mountain lions. Is one larger than the other? Is one a metric size? Can you use a puma when the manufacturer specifies a cougar? Can you? Can you? Hey, mister . . . -- Jay Beattie. |
#20
|
|||
|
|||
MTB randonneur
On 6/3/2018 10:20 AM, Emanuel Berg wrote:
Perhaps this was approached from the wrong angle, if one desires wide tires, perhaps one should get a 28" MTB steel frame and only have the gear loaded the same way? I've certainly seen a lot of people touring on a hardtail mountain bike, using narrower tires than the bike came with. But good luck finding a steel mountain bike these days. They exist, but they are expensive. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
randonneur | Emanuel Berg[_2_] | Techniques | 143 | June 7th 18 03:26 AM |
New randonneur handlebar | bcdrums | Techniques | 7 | June 17th 10 11:02 AM |
Vivente World randonneur | burnt | Australia | 6 | April 17th 07 08:39 AM |
mongoose randonneur | [email protected] | Australia | 1 | March 8th 07 11:07 AM |
Mongoose Randonneur LE Pro | noom | Australia | 1 | March 7th 07 10:43 AM |