Originally Posted by ThermionicScott

First things first, you need to put more air in your tires if they look like that.

I have what are probably the fattest 26"x1-3/8" tires on one wheelset, and they measure no wider than 36-37mm. A lot of cheaper tires in that size are much narrower. 26"x1.5" tires would probably be a little bigger, but it would depend on the model.