Bicycle Mechanics - Help with missing part (connects handlebars/front fork) Trek 930

Ok, my Trek 930 had been sitting in my parents garage for a year and they decided to take it to Mail Boxes Etc and have them ship it. They took it apart and when it arrived it was missing a piece that is necessary to turn the front wheel. Without it you can turn the handle bars and they just spin. I don't know what the piece would be called, or where I would get it.

I attached a picture showing where the missing piece is. If anybody could give me some advice as to how I can fix this, please let me know (or if it's even worth fixing, the bike is 5-6 years old).

Thanks..

I don't think that is what is causing your steering
to not work. What that hole in the stem is, I haven't got
a clue.
I'd look at tightening the stem steerer interface.


Marty

I think that hole is where a clamp used to be. It looks like unlike most other threadless stems, yours has a removable internal clamp. The basic design has two pieces of metal with quarter-concave cutouts facing each other and a bolt going through them. When the bolt is snug down the concave halves constrict and provide a clamping load on the steerer. The seatpost binder on my roadbike works in this manner and I believe the Thomson stems also use the same clamping arrangement. Unfortunately, I think you'll have to replace the entire stem as it would probably be extremely difficult to find a new clamp. Is there some sort of inscription on the stem to indicate the manufacturer? Perhaps try giving them a call.

Originally posted by khuon
I think that hole is where a clamp used to be. It looks like unlike most other threadless stems, yours has a removable internal clamp. The basic design has two pieces of metal with quarter-concave cutouts facing each other and a bolt going through them. When the bolt is snug down the concave halves constrict and provide a clamping load on the steerer. The seatpost binder on my roadbike works in this manner and I believe the Thomson stems also use the same clamping arrangement. Unfortunately, I think you'll have to replace the entire stem as it would probably be extremely difficult to find a new clamp. Is there some sort of inscription on the stem to indicate the manufacturer? Perhaps try giving them a call.


Yeah, that's exactly what it was. I know what it looks like because I've taken the bike apart before, but I just didn't know what it is called.

I guess I'll just look for a new stem, I don't think it's worth that much hassle to try and find the clamp.


Thanks for your guys help, I apprecaite it.

You can find stems online for as little as $4.00.

Try www.pricepoint.com www.jensonUSA.com www.supergo.com

Those are my "usual suspects" when searching for cheap parts.

L8R

Make sure you get the measurements for your stem correct before you start ordering. The important ones are stem length, stem angle, steerer tube size, handlebar clamp size and stem height (stack height). A lower stack height may be okay but you will have to remove/replace some spaces and cut down the steerer. Keep in mind that this will lower the position of the handlebar so if you like the current position, take that into account with appropriate stem length and angle. Too high a stack height will of course be a problem since you can't really grow your steerer.

That type of stem uses a pinch bolt, which is what is missing. They have kind of gotten phased out because they would deform the steer tube. As you tighten the bolt the two pinch wedges moved to the center and tightened against the steer tube. I would just replace the stem with a clamp style.

Here's one I found for supacheap! Shipping will cost more than the stem: http://pricepoint.com/product1109.html

L8R