An old Motobecane arrive for me in the mail today but the wedge for the stem didn't. I have the stem itself and the expander bolt. Should I just ask around at local shops for an old wedge? Does it matter that the SR stem is French sized? (22.0 in diameter, not 22.2).

yes in this case size does matter . did you look in all the packaging and box before you tossed it? did you check the steerer tube?

OH rats! I guess I was wrong.

It does not matter. A wedge for a 22.2 stem will work just as well. I've sanded lots of 22.2 stems to fit French steerers and I've never needed to sand a wedge.

Cool thanks for the info. Are wedges cut at different angles/depths/etc. or is a wedge a wedge?

I have found that most 22.2 wedges will work, I've also found some that will not.

as long as they are matching angles (55 degrees usually) a small difference won't matter.

New question -- LBS gave me an old wedge. It's kind of rusty. What are the chances it will introduce rust to the inside of the head tube? Does rust work like that?

Just grease it up and use it.

So contact with a rusty surface won't predispose and otherwise OK piece of steel to rust?

I ask partly in regards to this situation, and partly out of general curiosity.

Sand. Grease. Use.

Since it's a just a chunk of iron, you could just use a steel brush (or sandpaper as Zorro sez) to get the extra rust off. If you're really paranoid about it, coat it with 3-in-1 oil to convert the remaining rust, then grease and use.

However, my extraordinarily non-extensive materials science knowledge tells me that rust + iron does not yield more rust. The thing you have to worry about is water + iron, which does yield rust.

However, around here (and around bikes in general), nobody is really fond of rust. So dispense with it at will.

Well thanks for the advice, all. I sanded it to get the rust off. Then I realized it was a slightly different angle from the quill I have, and I *really* had to sand it. But it worked out in the end (I think..).

As ftwelder said, a small difference in angle doesn't matter. In my experience, quite a large difference doesn't matter.

Actually, that's not what he said. He said *as long as the angles match*, a small difference in *diameter* doesn't matter. It seemed to me from looking at what happened as I tightened the stem bolt that a mismatch in angles would be bad for the head tube, because the corner of the wedge would get tightened into it, rather than the whole side.

You're overthinking this. When I said "in my experience" it means I'm not just guessing. I've shortened stems with a hacksaw and the angle doesn't have to match.

Oh I don't doubt that it will *work* in that the stem won't come out of the head tube, but I still think it would be bad for the tube. Agree to disagree I suppose.

You think that the wedge will somehow end up at some odd angle? The stem bolt will prevent that.

I don't know why you bothered posting the question since you know it all.

All I can tell you is, when I screwed the wedge on as a test, using the stem bolt, it suck out at an angle, and it seemed like that would be bad. I'm not sure why you're taking offense at this. In any case, thanks for your and everyone's help as the operation was a success. Ciao.