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What is the difference in diameter? Can I substitute the 650s for road use of my mountain bike if it looks like I have about a half inch of adjustment available on my cantis? The adjustment is available to permit a slightly taller wheel than my 26"ers. Thanks
 

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Somebody has to know...

I just measured my 700 wheel set and I didn't get a match at 700 cm anywhere on it. What is being measured?
 

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Beetpull DeLite
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Head over to this link and read up. It sounds like you're just wanting to switch entire wheelsets, instead of switching tires, right? Because a 26 x Whatever tire won't fit on a 650 rim and vice versa.

I'd imagine that your plan would work...it doesn't hurt to try, right? Stick 'em on there and see what happens.

The 700 measurement is supposedly the outer diameter of the tire that's mounted on it. Of course this will be different for each tire, so it's not too useful.

http://sheldonbrown.com/tire-sizing.html
 

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NeoRetroGrouch
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Diameters: A 650c is 572mm and a 26" MTB is 559mm for a difference of 13mm. To gauge the difficulty, the difference between a 700c and a 27" is 8mm. - TF
 

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Thanks

I'm gonna give it a shot. Girchygirchy - that cookie took me right back to Woolworths Dept. Store in 1960. They used to call them Hawaiian cookies and they were about 3" in diameter. If I behaved, I got two or three. The Girl Scout Samoas are only a pale reminder.
 

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Arrogant roadie.....
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TurboTurtle said:
Diameters: A 650c is 572mm and a 26" MTB is 559mm for a difference of 13mm. To gauge the difficulty, the difference between a 700c and a 27" is 8mm. - TF
Umm....I'm pretty sure that 650c is a 597mm rim......

700c is a 622mm rim, 27" is a 630 mm rim.
 

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The dope on wheel sizes

1. the "700" in 700C means nothing any more. Neither does the "C". At one time, there were 3 sizes, 700A, 700B, and 700C. All were supposed to measure 700 mm with a tire mounted and inflated. The three sizes had a different tread width and sidewall height. Since all three were supposed to be the same overall diameter, the rims' bead seat diameters were all different. 700A and 700B went away long ago, leaving only 700C, and the confusion that either the number or the letter mean anything. They don't.

2. This weird convention still holds in the 650 world. There is still a 650A, 650B, and 650C. All three have been labeled "26 inch" at one time or another, and they're all different. 650A (590 mm) is the old Schwinn 26" road size, also the size for old Raleigh 3 speeds. 650B (584 mm) is an odd French touring size, undergoing somewhat of a revival now, due to the efforts of Grant Peterson and some other weirdos. 650C (571 mm) is the size often used for tri-bikes and TT bikes. 650B and 650C actually still seem to conform to the old convention, as all available 650B tires are fat, and all 650C tires are skinny. There's no technical reason for this, but it's true.

3. MTB 26" is in fact 559 mm. Life is made difficult by the fact that there are at least 6 different tire / rim sizes called "26 inch," and none of them are interchangeable. You need to know what you've got before you buy tires. Sheldon Brown's website is a good resource for this (and anything else you ever wanted to know about bicycles)

http://sheldonbrown.com/harris/tires/index.html

Hope this helps,

--Shannon
 
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