[Entrenador]

A few of us that roam around mtbr.com have an itch to try riding with 650B wheels, but lacking the disposable income to rush out and have one custom built, I'm wondering if there's another way to get there -- something perhaps more ideal than seeking a 26" wheeled frame that happens to barely fit the larger wheels.

If I had a 26" wheeled frame that I liked a lot, would it be feasible to have the rear dropouts replaced or relocated ~10cm further back from the original location -- say, using "longer" drop outs perhaps? Things I've considered: BB height +1/2" (tolerable, and perhaps in some cases, desirable), disc brake mount (could be relocated at the same time certainly).

Structurally, I'm guessing that moving the wheel back would increase the amount of stress on the frame at the dropout/CS and dropout/SS unions. Bad idea, or could this be done by the right person? What's right and what's wrong with this idea?

Thanks.
josh

 

[Walt]

Can be done, but...

...it'll cost more than you probably want to spend.

Save your pennies and get a new frame that's designed for the wheel size, or find a frame that will fit them (and that has a BB that's lower than you like, ideally) and cram 'em in. I believe the 650b board has a whole sticky of compatible frames/forks.

-Walt

 

[pvd]

650b=custom frame

Sorry. You just can't get around the fact that the frame really does have to be designed around the wheels. If you want to be cheap, stay with 26".

 

[rmb]

The Surly 1x1 is perfect for the 650B wheels and you can find one on the cheap. The wheels fit perfect with the BB height at approximately 12".

 

[Yogii]

Why would you have to move the disc brake mounts?

 

[byknuts]

if he welds the drops in a new location then the disc mounts need to move too.

105mm: a lot of the newer bikes with paragon-style sliders can fit 650B's with the wheel tugged back.
(kona five-O/cowans/explosifs for example)
again, like the surly 1x1, a no-cut/weld alternative.

 

[Cracked Headtube]

Single Speed? White IND Eno hub. Problem solved. I bought one and built it up as a 650B, but never used it. Only to see if it would work for a 26" frame w/o clearance for a 650B. In some frames it gave me just the room I was looking for. I have a Trek frame that fit the Quiasi-Moto, but not the 2.3 Neo, with the ENO I could fit the Neo.

 

[Entrenador]

Seems like there is more versatility with parts, fit, wheel sizes, etc when building SS bikes, but I prefer the versatility of gears when riding them -- quite the conundrum. Between an ENO rear hub and an eccentric BB, one would have a fair bit of adjustability. Just thinking aloud.

 

[Vlad]

I'm not a framebuilder and don't have much to offer except to ask--do you really need 650b wheels on a frame that you like so much? I mean, is the ride bad enough on 26" wheels to justify trying to make it work with bigger wheels? It doesn't make sense.