Choosing tire

Submitted by MMartinMM64 on Sun, 03/20/2022 - 06:26

Hello everyone,

I just start the repaire of a bicycle CCM : K77217

I need to change some part, but it's quite difficult for me too inderstand wheels and tire size.

 

  • Back wheels size is 16in. The old tire was 20 x 2 x 1 3/8

I understand that 20 is the outer diameter of the tire. 2 is the thickness : 20-2-2 = 16 : I am agree

 

  • Front wheel size is 18in. The old tire was 20 x 1 3/8.

Why there is only 2 dimensions for this one?

 

I need to replace the front wheels and tire. And the back tire.

 

but I am confuse with the new tire size...it's only 20x1.375, or 20x1.7 etc

For the back : wheel 16in, if I choose a 20x1.375 the inner diamter will be too large I guess. 

 

Is it possible to use 20x1.7 instead of 20x1.375?

 

Regards

 

Martin

 

 

 

2 Comments

Submitted by MMartinMM64 on Sun, 03/20/2022 - 06:33.

An other comment,

I found nice wheel for the front, but it is 20 in, is it possible to replace the 18 in by this one

After I need to add a tire, so increase the thickness...

Submitted by DUOMATIC on Mon, 03/21/2022 - 00:28.

That tire size is correct for some late 60s 20" bikes.

 

The back wheel is a smaller diameter and the tire is a larger thickness

but the outside rolling diameter is about the same. about 20"

 

20x2x1 3/8 is the tire you need to find. That is sometime hard to get.