# 1.75 vs 1 3/4" tires



## jd56 (Jul 27, 2012)

When I went to school...many years ago, I was taught that the following measurement was the same ( one using fractions and the other usining decimal)
1 3/4" = 1.75"

But, Bri mentioned to me yesterday that the Schwinn S-2 only takes a 1 3/4" tire are different than the other brand tires measung 1.75 used on non schwinn rims....I'm guessing

and I quote
Your Jag will probably take a S-7 wheel which is actually about an inch taller than a S-2(normal 26" rim), and will take a 26 X 1 3/4 tire...NOT to be confused with a 26 X 1.75(not even close..that's Schwinn's doing). 

So what is the difference in size?


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## rhenning (Jul 27, 2012)

Different size as said above.  The 26 numberis the outside diameter of the tire.  The wheel diameter for 26 x 1.75 tires is 559mm and the wheel size for 26 by 1 3/4 is 571 mm.  The two numbers are refered to in the bike world as bead seat diameter.  In other words the point the tires bead is when inflated on the wheel.  As said above 26 x 1 3/4 tires are for Schwinn middle weights and were used on S-7 rims.  S-2 rims were used on balloon tire bikes and middle weight Schwinns are not balloon tired bikes.  Roger


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## vincev (Jul 27, 2012)

JD,welcome to the Schwinn world! They will grow on you.lol


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## Andrew Gorman (Jul 27, 2012)

Here is Sheldon Brown's rundown on bicycle tire sizes:
http://sheldonbrown.com/tire-sizing.html
Read it and weep!


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