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The bicycle in question is a "Schwinn Women's Ranger 26" Mountain Bike". It has a slight play in the crank arms, stemming from the bottom bracket.

I tried taking the crank arms off, and I succeeded on the drive side, but stripped the threads on the left side. Now I can't take the crank arm off from the left side, which I think prevents me from disassembling the bottom bracket as well?

Question - is it possible to take out the bottom bracket, while still having the left crank arm attached to the spindle? What options do I have?

At this point I am willing to throw away crank arms, the entire bottom bracket, everything, I don't care, I just want the bottom bracket out and replaced.

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3 Answers 3

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As @ChrisH points out, destructive removal methods can be effective if you don't care about the parts in question.

An alternative is to use jacobs wedges to pry off the crank arm. Choose a set that has a gap that can handle the diameter of the crank spindle and thickness you need to get the crank arm off.

Jacobs wedges

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    I did once get a crank arm with stripped threads off in once piece, refitted it and then had to cut it off next time. So if you do use these - which look like a great solution (+1) - you should probably bank on getting the crank helicoiled or otherwise repaired (helicoiling the pedal interface is more common, but the BB interface should be doable as well)
    – Chris H
    Commented Apr 30 at 9:21
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I've removed a couple of crank arms with stripped threads. It's a bit tedious but doable on aluminium.

I just drilled repeatedly and hacksawed/filed away material until I had a slot into which I could get a crowbar quite deeply. Levering open and pounding from the back with a length of wood through the frame finished the job. Steel would be much harder of course.

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    Thankfully the cranks are aluminum
    – hyankov
    Commented Apr 29 at 16:34
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I ended up using a Unior square taper crank puller - 1662/4, to bite into the stripped threads and pull out the crank.

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