So I just noticed it becoming loose it hasn’t came off yet, do I need a new crank arm or can I just tighten it?
by Brilliant-State-1454
So I just noticed it becoming loose it hasn’t came off yet, do I need a new crank arm or can I just tighten it?
by Brilliant-State-1454
6 Comments
If it’s been loose a while then it’s probably ruined. Tighten it back up and if it keeps coming loose you’ll need another crank arm.
I’d tighten it first, undo the cap, then tighten the bolt inside.
You may also need a spindle.
New crank time. Bottom bracket spindles are much harder than cranks. Riding a loose crank deforms the hole and it’ll never be the same again. You might get a little bit more life out of it with a shim made from a sliver of a drinks can, but I wouldn’t recommend it.
The spindle isn’t moving so that crank arm is just barely hanging on. Unscrew the bolt holding the arm in, then use a rubber mallet to pound the arm into the spindle.
Tale as old as time. Steel cranks may reseat pretty well as others have noted. Aluminum crank arms are almost always ruined by the time you notice that they’re loose.
I had to replace the left crank on my old KHS mountain bike when I was teen, not once, not twice, but three times– for different reasons each time– but this was one of them.