so im building up a 2003 Mercian for my gf to tour on and ive run into a strange problem with the stem. i just bought a nitto technomic and it wont fit into the fork tube. its a 22.2 quill stem.. strangely other 22.2 stems fit no problem?! the bike is a 56cm so theres plenty of steer tube. it goes in about an inch past the wedge and then gets stuck. once again, other 22.2 stems go in all the way so theres nothing on the inside obstructing it. on that same note ive also discovered other 22.2 stems that didnt fit aswell.. im scratching my head on this one. should i sand down the stem? id really rather not mess with the fork. has anyone ran into this problem before?
for the record im a pretty experienced mechanic so yes i loosened the quill and lubricated the stem, etc.
thanks in advance!

It sounds like a tolerance issue, with the stem at the high end of the size range, and the steerer at the low end. Did you use a caliper to check the actual diameters of the steerer and stem. If it turns out to be only a few thousandths you can sand it or use some lapping compound, to work the stem in up to the desired depth, then pull and clean.

Do you happen to have a different fork to try the stem on. Obviously it won't make your problem go away, but at least you will know whether it is just an odd compatibility issue or if your stem really is out of spec. Since you just bought it, can you exchange or return it?

thats prettymuch what i figured. i did use calipers and the stem is almost 1 to 1 with the fork tube. its very close. i just looked up lapping compound. thats a great idea. thanks!

canam73- yes i tried the same stem on a different fork and there were no problems. its a custom mercian fork so i also checked for burring on the inside of the fork where they cut it. totally smooth. maybe the casting process on the technomic has something to do with a larger than normal diameter. ive done a little casting and there is a certian ammount of metal expansion that you have to account for. thanks for the input!

It could be some rust in the steerer tube which caused the fork to go out of spec.
a pipe or drain brush with some oil should clear it. You can drip some rust inhibitor, like linseed oil, into the steerer tube afterwards to prevent it from doing that again.

I think it is the stem. I just had the same problem with a Nitto Technomic stem. Pain in the rump, but it is just ever-so-slightly too big.

I put some time into sand paper and then emory cloth. Use some heavy tape to protect the area that will show from scratches. Messy, but it finally worked.

Once I had it down, I could see where the scoring showed from each effort to insert. That made the sanding process a bit more focused. Annoying, but it's the cheap Nitto.

+1 This was my first thought also. Turn the fork upside-down, and run a round wire brush into it, and see if it helps. Once you can get the stem to fit, I agree you should oil/lube inside the steer tube to avoid future issues.

Might just hone out the fork steerer. perhaps a brake hone, or one of those
flexible hones that looks like a stalk of Brussels sprouts.. a few thousandths,
put a shine on the inside of the fork steerer.

Of course one does slather on the grease before putting the stem into the steerer tube. HOWEVER, be sure to tighten it down carefully so that the grease doesn't assist it to suddenly spin and dump you ingloriously on the ground (as I just did about 20 mins ago... sigh).

that would be too much grease.

Welcome to club Tombay. Did you just join, or is this a renewal?

Don't take this personally, because we've all been there, if not in exactly the same way at least comparably.

But don't blame grease for your own failure to properly tighten and check the stem.

i sanded it down and buffed it back to a nice shine. it fits now! thanks for the help everyone!