It looks pretty hexagonal to me still. Pound an Allen socket into it and see if you can turn that.
fatoldbmxer on
It’s a crank arm pinch bolt. You could try vise grips or an extractor. If you can get a socket over it they sell special sockets for stripped bolts. You hammer it on and it grips rounded bolt heads, it should work here.
If it’s the bolt spinning either it, or the crank arm is stripped. Or the bolt snapped.
SkotCynwrig on
No way that bolt head is stripped. Looks crispy still. I bet your crank arm is stripped. In which case you need a new crank arm.
ballsplopmenacingly on
Pull and twist with vice grips
Fun-Try1379 on
This method has worked great for me in many occasions: use an angle grinder to cut the bolt into a flatheat and use one to take it out
randomlystable on
First, remove the sprocket so it doesn’t get damaged.
Next, put in the Allen key and turn it. Look in the other side so you can see the other end of the bolt. Is that end spinning also? If not, then the bolt has snapped, and you are pretty boned. If it is, then either the bolt or the cranks are stripped, or both. (If the cranks are stripped it is time for new cranks as eight spline cranks are not worth the time, effort, and cost to repair.) Now, find yourself something pretty thin but strong (screwdriver, punch, a stick) and use it to apply pressure to the underside of the bolt (the floor may come in handy here) while turning the Allen key. Hopefully, it will grab and come right out. If it comes out then inspect the threads of the bolt and crank arm to see if the arm is salvagable.
8 Comments
It looks pretty hexagonal to me still. Pound an Allen socket into it and see if you can turn that.
It’s a crank arm pinch bolt. You could try vise grips or an extractor. If you can get a socket over it they sell special sockets for stripped bolts. You hammer it on and it grips rounded bolt heads, it should work here.
rubber band method seems easy to try 1st
[https://www.wikihow.com/Remove-a-Stripped-Allen-Screw](https://www.wikihow.com/Remove-a-Stripped-Allen-Screw)
If it’s the bolt spinning either it, or the crank arm is stripped. Or the bolt snapped.
No way that bolt head is stripped. Looks crispy still. I bet your crank arm is stripped. In which case you need a new crank arm.
Pull and twist with vice grips
This method has worked great for me in many occasions: use an angle grinder to cut the bolt into a flatheat and use one to take it out
First, remove the sprocket so it doesn’t get damaged.
Next, put in the Allen key and turn it. Look in the other side so you can see the other end of the bolt. Is that end spinning also? If not, then the bolt has snapped, and you are pretty boned. If it is, then either the bolt or the cranks are stripped, or both. (If the cranks are stripped it is time for new cranks as eight spline cranks are not worth the time, effort, and cost to repair.) Now, find yourself something pretty thin but strong (screwdriver, punch, a stick) and use it to apply pressure to the underside of the bolt (the floor may come in handy here) while turning the Allen key. Hopefully, it will grab and come right out. If it comes out then inspect the threads of the bolt and crank arm to see if the arm is salvagable.