crank with naff threads
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Usually the trick is to ride it round the block (up a steep hill is best) and it rapidly loosens. I'm not sure how well that works with Octalink compared to square taper. Loosen the crank bolt a few turns (but leave it on so that the crank cannot fall off and do you a mischief).
Failing that a car bearing puller is another solution.
Failing that a car bearing puller is another solution.
RickTheUncivil
Old School Grand Master
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Bearing puller should work if you can get the right size to fit. Push the axle in the centre, pull around the edges of the crank. This is tricky on the drive side obviously but not impossible with the correct amount of faffing.
Failing that the loosen bolts and ride method can work but as above be careful not to do yourself an injury in the process. Done tjis more than once.
I suppose a third option would be to push, whack it from behind with a hammer and block of wood shaped to fit. Pretty sure I have done this at dome point too!
Bearing puller should work if you can get the right size to fit. Push the axle in the centre, pull around the edges of the crank. This is tricky on the drive side obviously but not impossible with the correct amount of faffing.
Failing that the loosen bolts and ride method can work but as above be careful not to do yourself an injury in the process. Done tjis more than once.
I suppose a third option would be to push, whack it from behind with a hammer and block of wood shaped to fit. Pretty sure I have done this at dome point too!
old_coyote_pedaller
MacRetro Rider
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Don't think the "loosen the bolt and ride " method is a good idea with splined type BBs. With a taper BB as soon as the crank comes loose it is free of taper but splined cranks/BBs have to be pulled straight off, if not there is a danger of splines of BB damaging the crank arm as it will be forcefully wiggled about by pedaling action. The internal splines on crank will get chewed by the much harder steel splines on BB.
This is the post I made about a method I came up with to remove an FSA splined crank arm,
And my reply when it was suggested to just loosen bolt and ride,
So, since the OP said he wants to keep the cranks I wouldn't go with the loosen bolt and ride method.
Don't think the "loosen the bolt and ride " method is a good idea with splined type BBs. With a taper BB as soon as the crank comes loose it is free of taper but splined cranks/BBs have to be pulled straight off, if not there is a danger of splines of BB damaging the crank arm as it will be forcefully wiggled about by pedaling action. The internal splines on crank will get chewed by the much harder steel splines on BB.
This is the post I made about a method I came up with to remove an FSA splined crank arm,
It's a Giant Trance X3, 2008 I think, the extractor threads on NDS crank had stripped so crank arm was looking like getting destroyed to remove it to replace knackered BB. So when I saw him at the weekend last he asked me what could be done to fix his bike, idiot that I am I said "I'll get it off nae bother" :roll: . Tried a method that had worked on an old Shimano crank, a ball joint splitter, widnae fit due to BB having spacer for arm to hold against. So tried a bearing puller that locks the pulling arms in place but due to steel puller and aluminium crank the puller was just sliding and scratching crank. Feck.
Then I had a bright idea of somehow bolting/fixing another crank arm that had good extractor threads onto fecked one. Removed pedal then bolted the 2 crank arms together with a spacer between pedal threads so that BB ends of cranks were in line and square to each other. Rummaged in shed and found a 2" diameter exhaust clamp, fitted this with the u-bolt part around the back of stuck crank with a big socket in hollow in the back of crank to prevent damage from the u-bolt, the other part of clamp, the pressed steel bit, just clamped up against the "extractor" crank. Tightened it all up, it wasn't moving. Had to cut down a longer bolt to about 40mm to fit inside the bolt threads on BB so that the extractor could reach being too far out from the BB axle.
So the moment of truth arrived, tightened extractor and the 2 cranks were no longer tight together, did the clamp nuts up tighter but then noticed that the cut down bolt in BB had crumpled with pressure. Replaced it with slightly thicker bolt which didn't bend as much, gave the crank arm a bit of a tap with tool number 1 and off it came. Apart from scratches which are merely cosmetic and a wee dent from big hammer the crank is OK and can go back on with new BB.
For future use I'll find a proper high tensile steel bolt that will thread into BB axle to sort the bending of the bolts made of cheese I had to hand.
And my reply when it was suggested to just loosen bolt and ride,
So, since the OP said he wants to keep the cranks I wouldn't go with the loosen bolt and ride method.
davidj
Senior Retro Guru
I only have square taper BBs so forgive me if this is a daft idea. Can you remove the none drive side crank and then extract the drive side and BB as a complete unit? If so then using wood blocks to protect the back of the drive side crank/chain rings suspend it so the BB is vertical and use a metal rod as a punch and tap it out with a hammer..
