kirke

Title says it all: are 650c rims and 26" rims the same diameter?

My partner is considering buying a new Soma mixte frame, and the size she needs is spec'd with 26" wheels. The only 26" wheels I know of are intended for fat MTB tires, which she does not want. So, she is thinking of building up a wheelset for the bike with 650c rims so she can run normal 23c road tires. That is, so long as 650c and 26" are close enough to not effect the handling of the bike.

Thanks!

adamrice 

Not the same. 26" wheels are 559 mm in diameter; 650Cs are 571 mm. The difference probably wouldn't affect your handling significantly, but you'd need to make sure your brakes could handle the 6-mm offset, which probably wouldn't be a problem.

However, there's a variety of 26" rims out there, and there are tires for them as skinny as 1.3"--in fact, I just checked, and Schwalbe has 26"ers as narrow as 20 mm. As a rule, you'll probably have an easier time finding tires for 26" than for 650C.

kirke

Awesome. Thanks so much for the link. As always, I suppose I should have checked Sheldon first.

I ask because 26" rims are something that I have never dealt with before. I guess I assumed they were a MTB-only wheelsize, although it seems they are popular for touring and commuter bikes as well.

Is there a decent 26" wheelset out there that would be good for a commuter bike and would accept skinnier 26" tires?

JiveTurkey

Newer MTB rims are much skinnier than they used to be, so they can handle skinnier tires. On average though they are still a little wider than ones specifically made for road tires.

Once again "There's a Sheldon link for that": https://sheldonbrown.com/tire-sizing.html#width

You can find inner rim width specs of many rims out there, then consult the above chart for compatible tire widths.

Jeff Wills

-Ish. It can be equally frustrating to try to find 650C or very narrow 26" tires. Online it should be no problem, but if you're on a tour and stuck in West Antler Branch, Montana, probably not.

If this is the frame the OP is considering: https://www.somafab.com/bvista.html I'll bet it's built around 26" (ETRTO 559mm diameter aka MTB) wheels, not 650C. That's based on the brake reach and dropout width specs. Bikes built for 650C wheels usually have very short reach brakes and are built for "road" 130mm width hubs. For that frame, any light wheelset built for rim-brake mountain bikes will fit or a set of custom wheels built on Velocity Razor or Fusion rims would be the right stuff.