I picked up a 24" Schwinn Speedster from a local guy via Craigslist for 50 bucks. I'm trying to fix it up for my girlfriend. It was in great shape, so I don't have to do much to it.

The problem is the wheels/tires. The original tires were cracked, and completely shot.

Best I can tell, the rims are Schwinn S7 rims, which means they should hold 24 x 1-3/4 tires, which is what the original ones said on the side of them. The original tires have since been disposed of, so I do not have them to measure.

I already learned my lesson about 24 x 1-3/4 vs 24 x 1.75 and how they are completely different, but I've tried both, and I just can't get the 24 x 1-3/4 tires to fit onto the rim. I can't even get the first side of the tire onto the rim so I can put the tube in and the rest of the tire. I can get it about 2/3 - 3/4 of the way on, but it seems like I need another inch or so.

Is there a trick to this tire size? Am I completely wrong in the size, even though that's what the originals said on them? Should I take the tires/wheels to an LBS and have them install them for me?

I'm at a loss. HELP!!!

As a side note - I checked Sheldon Brown's site, and I verified, thanks to his instructions on measuring the bead-seat circumference of the rim, that these are definitely 24 x 1-3/4 rims, but he also suggests that 24 x 1-3/8 will fit.

My mother in law has the same bike and I just 2 weeks ago put new tires on it. Those are S-6 rims and require 24 x 1 3/8 S5/S6 Schwinn specific tires. Welcome to the wonderful wacky world of Schwinn sized tires. Roger

Ahhhhhh!!!! I've been about to tear my hair out for the last 2 weeks. Good thing I'm only spending 9 bucks a tire to play this ridiculous game. Alright, I'll look for these. Thanks!

It's a tough one because I can't find much online about this bike. I have a Raleigh Sprite that I found WAY TOO MUCH info on, but this Schwinn is apparently not so common.

Thanks again!

So even though they're barely different (a tiny bit less wide, mathematically), there'll be that much of a difference diameter wise? wow.

Which one of these should I go with, do you think?

Pyramid Tire 24 x 1-3/8 Black/Black Road K40 --- $3.35
https://www.amazon.com/Pyramid-Tire-1.../dp/B000AO7I0G

Kenda S-5 24" x 1-3/8" x 1-1/4" Black Steel --- $9.62
https://www.amazon.com/Kenda-S-5-1-3-...ef=pd_sbs_sg_8

Pyramid Tire 24 x 1-1/4 (Schwinn S6) Black Tread / Gum Wall Street K23 --- $8.48
https://www.amazon.com/Pyramid-Schwin...ef=pd_sbs_sg_9

Thanks!

The Schwinn 24" S-5 and S-6 rims are oddities in that although they are supposedly meant for 24 x 1-3/8 nominal size tires, which would normally fit a rim with a 540mm bead seat diameter, the Schwinn rims have a larger 546mm bead seat diameter, which normally corresponds to 24 x 1-1/4 or 24 x 1-1/8 nominal size tires. Schwinn tire sizes are unique to Schwinn. The Schwinn 24 x 1-1/4 tire (ISO 20-546) is meant for an S-6 rim and 24 x 1-3/8 tire (ISO 22-546) is meant for an S-5 rim. I would guess that the Kenda would work.

Yeah, that sounds about right. The wheels I have are 22" w/out the tires, and the bead seat is about 1/4" less on each side, so that'd make it 21.5", which is 546mm. Hmm. Now, to find tires that are going to fit. Hard to tell with some of these, as they don't always list the bead diameter.

The 24 x 1-3/4 I have are literally a couple inches too small, bead diameter-wise, when you're trying to put them on the rim. If I lay the tire down on the ground, and set the rim on top of it, however, it does look pretty close. There's just no way I can get them on there, so I believe you're right - I just don't want to order yet another set of tires, and have them not fit. Heh.

Thanks for your help, and please - throw any more ideas you may have my way!

Telcoserf the ones for my mother in laws bike I got from Niagara Cycle. They are Pyramid labeled but the side wall says Kenda. Make sure you buy the ones for S-6 rims. They were between $25 and $30 with shipping for two. Roger

The 24 x 1-3/4 tires are meant for a Schwinn S-7 rim (ISO 25-521) with a 521mm bead seat diameter, which is 25mm or a full 1 inch less than the S-5 or S-6 rim. You simply cannot mount these tires on your rims.

just ordered a set of s5/s6 tires for it. too bad i couldn't find any whitewalls, but thanks everyone for your help! now i know the wonderful quirks of restoring a schwinn!