Bicycle Mechanics - 26 3/8 wheel conversion

I have an old 10 speed with 26 3/8 wheels and want to put more narrow wheels on it. The 26 3/8 rims are pretty hard to find. I am wondering if the 700c rims would fit the frame/fork. With the current set-up, there is quite a bit of room vertically between the tire and the frame/fork. Anyone have any expericence with this type of conversion? I am also thinking of converting this bike to a fixed gear. Any advice would be appreciated.

Going from 26" to 700 cm (28") is a big jump.

First, measure your chainstays and seat stays to be sure their is enough room for 700 cm wheels plus some extra space. I like at least 15 mm extra space though some bikes have less.

You will probably also have to replace your brake calipers. It is doubtful that the original calipers would have enough range to accomodate both 26" and 700 cm wheels.

New road hubs might or might not fit in the new frame. It is possible to bend your stays apart to accomodate different hubs, but if you go too far, the freehub may rub against the chainstays or the dropouts.

Good luck.

Ask Santa for a roadbike.

I have actually done this, BUT I had old bikes to cannibalize for parts. I put 700c wheels on my daughter's inexpensive dept store "mountain" bike to make an easier rolling machine for my wife to ride. I wanted to buy her a new bike or at least a decent used one, but she refused. There was plenty of room in the frame and fork for the additional diameter. The only difficulty was the brakes, which were too long. I took a pair of Weinmann brakes off of an old Trek 10-speed, which were just right EXCEPT that the mounting bold for the front brake was too short. So I took the mounting bolt from the original brake and rebuilt the Weinmann on it. Works like a charm.

Now having said all that, let me throw out this disclaimer. I may have been lucky. According to ISO standard measurements, rims over the years that were nominally 26 inches varied in diameter from 571 to 597 mm. 700c rims are 622 mm. So the difference in radius could be over an inch.

If you have a 700c wheel or can borrow one, stick it on and see if there is enough vertical adjustment to move the brake pads up far enough to reach the larger rim. If not you will have to put different brakes on. You could measure from the brake mounting hole to the rim to see how much reach you need then look for brakes that are the right siz.

Originally posted by chungachanga
I have an old 10 speed with 26 3/8 wheels and want to put more narrow wheels on it. The 26 3/8 rims are pretty hard to find. I am wondering if the 700c rims would fit the frame/fork. With the current set-up, there is quite a bit of room vertically between the tire and the frame/fork. Anyone have any expericence with this type of conversion? I am also thinking of converting this bike to a fixed gear. Any advice would be appreciated. Current 26" MTB wheels may be an easier option,with a number of narrow tire options

Except that the 26" ATB wheel is smaller diameter than 26 X 1-3/8 and the brakes probably won't reach even with long reach Weimann/DiaCompe brakes. Try a few out if you have a bike or two you can borrow from for a test.

Agreed -- MTB wheels will definitely not work with your brakes.

What about 26" racing wheels? Otherwise, look for 26 x 1-1/4" (an old British club size) tyres to fit your 26 x 1-3/8" rims.

Originally posted by John E
Agreed -- MTB wheels will definitely not work with your brakes.

What about 26" racing wheels? Otherwise, look for 26 x 1-1/4" (an old British club size) tyres to fit your 26 x 1-3/8" rims.

Good thinking, John.

Hey, you know what. I have some old 26" inch wheels I can sell you for $25.00 total for the set (front and back). They came from an 1970's vintage ten speed. The rear wheel has a five-speed freewheel and everything. Contact me through the forums.

What a nice guy. I feel like Santa.