To support my bicycle and motorcycle habits, I garbage pick old bikes,
fix them up, and sell them.
For the most part they don't need much more than a squirt of oil and a
patched tube. Lots of them have tire-rot as well.
I picked up a Schwinn Collegiate coaster brake bike that was in decent
condition. There was literally around 1/4" of mung growing off the
chain.There's a bit of rust on the rims, stem and bars, nothing a
quick brushing couldn't handle. The tires were totally shot, with
large chunks of the gumwall cracking off onto the floor. I was able to
make out some basic info: Made in USA, 26 x 1 3/8, Schwinn.
I looked through my supply of decent-condition tires and found a pair
of 26 x 1 3/8 that came off of a Raliegh 3-speed that had been crushed
by a car. (Don't worry, I live in NYC and the bike was locked to a
pole but had fallen over and into the path of a parking car.)
I popped off what was left of the old 26" tires from the Schwinn
(which were the originals and with good tread, btw), and proceeded to
install the Raliegh's 26s.
20 minutes later, I'd broken two plastic tire levers. I tried the
other tire, thinking that maybe this happened to be an unusually tight
bead. I looked at the rim but found no info. Then I found another 26 x
1 3/8 gumwall from a different bike, some dept store Spalding or
something. This tire seemed more promising.
30 minutes later, I did something I've considered close to a cardinal
sin ever since I was a teenager working on my BMX bike. I commissioned
a flathead screwdriver to the purpose of installing the tire. "The
right tool for the right job" only holds up for so long.
After enough grunting, groaning, and cursing to make my GF stop asking
me if I was okay, I got one side of that sucker on. It didn't look
healthy, though. The other side...HAH! No dice.
Tried an mtb tire that I knew sat loosely on my Mavic 121 rims. Again,
no dice.
FINALLY, I took another look at the chunks of gumwall still attached
to the threads. Something about "S-5 or S-6". Did some googling and,
lo and behold, Schwinn did their own tire sizing.
A quick trip to the LBS for a S-6 tire and $10 later I all was in
working order.
Yeah, I'm sure this is something a lot of you guys have known about
for a long time, but there's always something new for me.
/s