ac29593

On my road bike I over torqued the screws on my stem to the point where I stripped the screw going into the star nut and could not get the stem off the bike (stupid, I know). I had to have the screw drilled out which a bike mechanic did for me since I do not have the tools or experience not to damage anything worse. He showed me the aluminum tube that runs down the fork and noted that since I put so much force on the bolts a slightly bent the top of the tube so that it was now not perfectly round.

What I was told is that I could have done damage to the tube since it is fragile, to the point where it could crack turning into a dangerous outcome from loss of steering. He said it was fine now, but something I should keep my eye on.

Since there is no damage right now, is this something that could become worse and something that I should be concerned about, or am I ok?

Thanks for any feedback.

noise boy

Your mechanic is sort of right. If you overtorqued the bolt going down into the steerer enough to take the tube out of round, you have essentially broken it. Once aluminum has stretched, there is no going back, it is on the road to failure. A couple of things, the bolt on top of the stem only adjusts the preload on the headset, it doesn't hold the stem on, that is what the pinch bolts on the stem are for. You only have to tighten the top bolt enough that there is no slop in the headset. If you are going to continue wrenching on your bike, I would suggest you get an inch-pound torque wrench (sears has a nice clicker one for less than 100.00 vs. 250 for the park tool version), and a copy of a good bike maintenance book. On the subject of your fork, it could fail tommorow, it could go a thousand miles, it could never fail, personally I would probably replace it just to be sure, catastrophic loss of steering is never fun.

ptle

Do you have enough space to to cut off the weak aluminum part, and lower then lower the stem?

NiMO189

+1, this essentially takes care of anything that may come up down the line.

That being said, us mechanics tend to be very cautious about any potential problems that are spotted. Most likely, this won't lead to problems any time soon, but in the advent that it does, the mechanic commented on it and is released from liability regarding their work on it.

ac29593

Yes, where I tightened was right near the top, and it was only noticeable when I looked closely, not completely warped. It does "seem" fine for now, just wasn't sure if this was something heavy riding will make worse.

Thanks for the responses and the info.