Originally Posted by
ghostm42
So, when I buy a quill stem online, am I supposed to buy a 1" one or a 1 1/8" one? I'm guessing a 1 1/8" one. As if it's not confusing enough, the 1 1/8" ones are usually labelled 25.4mm.... which is equal to 1". Is this right?
Yeah, 1 1/8" threaded is a little rare, they're out there though.
You'll need a 1 1/8" stem. The 25.4mm you're seeing is likely the stem clamp diameter. You need to match this to your handlebars. Unfortunately Bikepedia doesn't have this info. Chances are very good that your bars are 25.4.
25.4 and 31.8 are the two sizes that cover almost all MTB stem/bars out there. It's pretty easy to tell the difference if you're used to 25.4. If not, snap a pic and someone could probably tell by looking.