Bicycle Mechanics - Frame geometry - 26" -> 700C

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View Full Version : Frame geometry - 26" -> 700C


BikeManDan
08-03-07, 11:30 PM
I have a 2004 VooDoo Wanga with a Surly rigid fork on my hands that is my current project. Its going to be my commute bike with slick road tires, disc brakes and internally geared hub.
I have a 26" wheelset on it right now with 1.2" wide tires and it just plain looks goofy. Tires look tiny because theres so much clearance on the frame. The frame was built with super wide knobby mountain bike tires in mind so this makes sense.
So it would make sense to me to then switch to 700C wheels with narrow tires and that would bring me back close to spec for frame clearance and geometry. Since I'm using disc brakes, no worries about brake reach.

Is this sound thinking? Any holes in the plan?


PDXJeff
08-04-07, 01:37 AM
I'd be surprised if the 700c wheels didn't hit the seat stay bridge or even the chain stay bridge. The hubs on th 700c wheel are probably a different width than the 26in wheels too. I think the rims would need to be built to a Mt bike hub. It would be sort of like a 29 inch Mt. Bike. 29r's are specifically built to accommodate a wheel with a circumference that large though.

This is a good, wide 26 in commuter tire. They've been around for years.
http://www.biketiresdirect.com/productdetail.asp?p=COTAC&gclid=CITq-aus240CFQkGhgod-3aEaw

Good luck, looks like a nice frame.

urbanknight
08-04-07, 01:41 AM
iirc the overall diameter of a 26" wheel with a fat tire is about the same as that of a 700c wheel with a skinny tire, so you should be fine there. As mentioned above, the hub spacing might be different, but some tandem wheels have the wider spacing you need, or you could build your mtb hubs up with road rims.


HillRider
08-04-07, 06:48 AM
Typical 700c wheels are built on 130 mm rear hubs and MTB wheels are on 135 mm rear hubs. You could add spacers to a 130 mm hub to make it fit. However, I'm not aware of any "road" hubs with disc brake mounts so you will likely have to use MTB hubs anyway and have the wheels custom built.

FlatFender
08-04-07, 09:26 AM
Dooo Itttt

BikeManDan
08-04-07, 10:03 AM
Oh forgot to mention that, I'm building the wheels myself. I bought a Shimano Alfine hub from Germany so a wheel build is a must. I'll also now build a front wheel with a MTB disc hub

operator
08-04-07, 10:36 AM
I'd be surprised if the 700c wheels didn't hit the seat stay bridge or even the chain stay bridge. The hubs on th 700c wheel are probably a different width than the 26in wheels too. I think the rims would need to be built to a Mt bike hub. It would be sort of like a 29 inch Mt. Bike. 29r's are specifically built to accommodate a wheel with a circumference that large though.

This is a good, wide 26 in commuter tire. They've been around for years.
http://www.biketiresdirect.com/productdetail.asp?p=COTAC&gclid=CITq-aus240CFQkGhgod-3aEaw

Good luck, looks like a nice frame.

There are more frames that accept 700c wheels that were originally 26" than not.

ib4it
08-04-07, 02:22 PM
don't forget to post pic's