On Oct 10, 6:18 pm, JeffWills <
[email protected]> wrote:
> On Oct 10, 5:05 pm, Pilgrim <[email protected]> wrote:
>
> > Hello, I have a 1975 Schwinn Sports Tourer frame which would have
> > originally been equipped with 27" wheels. The chainstays seem rather
> > narrow, but I would like to put 26" mountain bike wheels and tires on
> > it. What is the maximum tire width that will fit this bike, or how
> > should I measure it myself to determine this?
>
> You can measure for yourself by finding the point roughly 12 1/2" from
> the axle on the chainstays and then measuring the distance between the
> chainstays. IIRC, you should be able to fit a 1.75" wide tire in
> there- but that'll be a tight fit. A 1.5" tire might work better, but
> it's not much fatter than the original 27 x 1 1/4" tire.
>
> Also, you'll be dropping the bottom bracket by almost 1 1/2". This is
> drastic, particularly since the Sport Tourer didn't have a high BB to
> start with. I'd expect to be banging pedals on the ground in even the
> mildest turns. If you can put up with that (I did, for a while), fine.
> It's just a consequence of building a mongrel bike like this.
>
> A better choice would be to convert the bike to 700C wheels, which are
> almost the same diameter, and have a much wider range of tire sizes
> available. 700 x 40C tires should fit, and you might be able to use
> your original brakes.
>
> Jeff
Good points Jeff, I hadn't thought about the effect on the ride
height. That could be annoying. I don't have to worry about using the
original brakes because I got the frame bare, and I actually kinda
prefer a coaster brake. Don't worry, I'll have a front brake. Just
bought a Surly 1X1 fork with canti pivots for 26" rims so that
shouldn't be a problem. Gotta admit, part of me wants to scrap the
Schwinn, and just finish the job with a Crosscheck frame, but lets do
this cheap. After all, it's a mongrel :-D
So is chainstay bending an option? A friend of mine said that he had
managed to spread his a bit to fit a wider axle, but could the same be
done at the seatpost to increase tire clearance? I know somebody's
gonna jump my case about this, but let me put it this way. I live in
San Francisco, and I frequently dash between cars at intersections. If
this is less dangerous to my health than that, it probably won't
bother me. I paid $35 for this frame, and I can always take a bus
home. So lets get experimental!
One thing to note is that I've already cut off the crossmember that
holds to chainstays together at the seatpost, it was a kickstand. I
plan to braze another piece of metal in there for strength, but before
I do that it should make bending the chainstays a little easier.
"Mongrel bike", I like the sound of that :-D