Trying to do some work on a neighbours bike and when I came to remove the crank after removing the retaining bolt I found that the inner thread on the crank arm had been totally stripped by someone.

Any tips on removing the crank arm now that I can’t use a crank tool (I have tried it just pulls straight out)?

Remove bolt.
Ride around in circles for a bit.

Speed process up by pouring boiling water over crank arm.

Had to use an angle grinder on the wifes old bike crank that was ‘welded tight’ over years of not being serviced and stripped thread.

There is a special VAR tool that cuts a larger puller thread and uses a larger puller. I’ve got one in Glasgow, other good shops also exist 🙂

nice to see you back Ben.

Thank you 🙂

Mini ball joint splitter

Or maybe

Trouble with ball joint splitters is that you need to be careful you don’t damage the bottom bracket shell.

There’s another VAR tool which clamps to the crank arm itself, and then pulls. I’ve got one of them too – can you tell I’ve got a bike tool fetish?

Which arm? Can you get teh other one off? If it’s the left arm stuck, depending on the type of bb, you can remove the right bb cup and back it off against the cup. Go carefully though, if it’s seized on to the spindle you could strip the threads in the frame, then you have a much bigger problem.

Three arm clutch puller, if “wot Brant said” doesn’t work.
You could also try a few sharp taps with a hammer, knocking it back ON not off.
This might break the bond.
If all else fails slot it with a hack saw and spread it with a chisel

hacksaw method doesn’t take too long.

Swearing and just wacking it with a big hammer is always a good fall back too. Impresses girls too.

+1 for the ball joint splitter

+1 for the big hammer

Thanks for the tips everyone, the winning combination was Plus Gas, hot air gun and a crowbar. 😀