Bicycle Mechanics - I've destroyed my stem after flipping it....how to fix?

Flipped my stem, no problems or so I thought), wee bit loose on a roughish ride, got it home, and loosened it all, to redo it properly.

Bad idea....

It's an aheadstem - one bolt in the top, two in the side. I've attached a pic - apologies if this is "STEMS 101" to all of you! :)

My problem is, the two side bolts tighten, but the whole thing is still very loose.

Only the top bolt actually tightens the stem at all, and I read somewhere that this is wrong....

Anyway the two side bolts I tightened too much, and now I can't get them out, or any tighter. DEad.

I reckon it's a replacement stem (no probem - my mistake - learning....) but I don't want to fit it wrongly! I can get that today.

So, how to fit properly?


p.s. I reckon my whole thing allowed my to steer originally (after I flipped it) by the top bolt alone.... I don't think that's good.... I don't think they sidebolts were tight at all...

I'm not sure what you've done but consider doing two things:

1. Before heading off to the bike download Chapter 11 of Barnett's Manual and read pages 11-21 and 11-22 to familiarize yourself with the step-by-step instructions for removal and installation of threadless stems/headsets. Here is a link:
http://www.bikeforums.net/barnettes/barnetts_ch11.pdf

2. Make sure the stem is the right size for your steerer tube and or that you didn't lose any sleeve that may have originally been inserted in the stem. A 1 1/8" stem is often time used on 1" steerer tubes by using a sleeve. Without the sleeve, there's no way you'd be able to pinch the stem's binder bolts (what you called the side bolts) enough to secure the stem to the steerer tube.

FWIW: The "top bolt" is actually called the adjusting bolt and it's sole purpose is to set the preload on the headset's bearings. If it's tight enough to hold the fork in a fixed position there is a very high probability that you may have damaged your headset's bearings or races -- depends on what type of headset, how far your rode, etc....

You might want to take your bike into a bikeshop and have them take a look just to be sure everything gets squared away before you start riding again. A damaged headset can make for a very unstable bike.

Just my .02.

Originally posted by livngood
I'm not sure what you've done but consider doing two things:
Just my .02.


Cheers.... looking at those pages now...

Originally posted by livngood
2. Make sure the stem is the right size for your steerer tube and or that you didn't lose any sleeve that may have originally been inserted in the stem. A 1 1/8" stem is often time used on 1" steerer tubes by using a sleeve. Without the sleeve, there's no way you'd be able to pinch the stem's binder bolts (what you called the side bolts) enough to secure the stem to the steerer tube.



It's a 1 1/8" stem, and tube. It just was NOT tightening with the binder bolts, at all.



The "top bolt" is actually called the adjusting bolt and it's sole purpose is to set the preload on the headset's bearings. If it's tight enough to hold the fork in a fixed position there is a very high probability that you may have damaged your headset's bearings or races -- depends on what type of headset, how far your rode, etc....


It wasn't that tight, but certainly, the forks certainly sort of "fell" into the centre position, like there was a groove that shouldn't have been somewhere....

It's sounding expensive.... ;)

Do yourself a favor and visit the lbs, for your own safety.

-Ryan

Originally posted by BikerRyan
Do yourself a favor and visit the lbs, for your own safety.

-Ryan


Beginning to sound like a cunning plan.... :D