[Note: this is #17 of a series of 20]
To truly become a wheel guru, you need to understand more than just how to build. Crucial to wheel performance is your choice of tire and there’s more to tire selection than many so called experts know.
The ISO system is an excellent beginning to the question of sizing. Tires are given an ETRTO number that designates the rim diameter for which they’re intended. Our 700C standard is ETRTO 622. So a 622 tire will fit a 622 rim. Likewise, for MTB, the standard is ETRTO 559. Match these numbers and you’re on pretty safe ground.
This completely overlooks the assembled size. Clincher tires become larger or smaller depending upon the rim on which they are mounted. You can appreciate the absurdity of buying a particular tire size and assuming this defines its inflated dimension. Read more →