Bicycle Mechanics - Quill stem & steerer tube problem

I got a Nitto Technomic Deluxe stem today and am having some trouble with it. I can only get it in to about the minimum insertion mark. The original stem will go in farther. I figured that maybe I had slightly bulged the steerer tube or something, but seeing the thread on tapered steerer tubes makes me wonder if that is what is coming into play. The wedge of the original stem is shorter overall and rounded at the bottom while the Nitto's is more squared off. The short side of the original wedge is also very short while the Nitto's short side is maybe .75 cm. Wish I'd seen the tapered steerer tube thread earlier because I've already taped up the handlebar. Are wedges interchangeable between stems? I didn't think to try the wedge from the original stem on the Nitto stem, so I don't know if it would make a difference anyway, but if it's safe to switch them I'll give it a try.

Can you see down inside the steerer tube with a flashlight? There might be a bunch of corrosion/crud inside that had built up right below the wedge on the old stem. You could probably get in there with some sand paper or even a bearing scraper and remove the corrosion/crud.

Before swapping wedges, measure the angle on the wedge and the stem and make sure they match up like the original combo did. This will be an easy task if you have an optical comparator available but you could probably get a decent estimate with a protractor.

Before swapping wedges, measure the angle on the wedge and the stem and make sure they match up like the original combo did. This will be an easy task if you have an optical comparator available but you could probably get a decent estimate with a protractor.

Or you could put the wedge on the stem and eyeball it to see if it engages evenly as it is tightened.

An optical comparitor..? :rolleyes:

Or you could put the wedge on the stem and eyeball it to see if it engages evenly as it is tightened.

An optical comparitor..? :rolleyes:

You know, you have a good point considering I did suggest eyeballing the angle using a protractor :o But, I'd hate to see a half to 1 degree angle difference that someone missed using the eyeball method ruin the guy's steerer tube. I just happen to have a comparator readily available at work so the suggestion came naturally. I realize not everyone has these things around though.

You know, you have a good point considering I did suggest eyeballing the angle using a protractor :o But, I'd hate to see a half to 1 degree angle difference that someone missed using the eyeball method ruin the guy's steerer tube. I just happen to have a comparator readily available at work so the suggestion came naturally. I realize not everyone has these things around though.

see if the new stem bolt will fit the old steerer tube expansion nut. If it does then use it.