Thread stripped out of crankset :O(

[deano69]

I have a fairly new set of alivio crank / chainrings on my bike and decided today to take then off strip down the bike as frame is being powder coated.

The opposite side of the chain rings came off easily with the crank puller tool but the chain ring side .....NOT,
I threaded the puller tool all the way in till tight then turned the other part to release from square spindle then all of a sudden the whole tool pulled out through the threads stripping them and leaving the crank well and truly on there :O( .

Now how do I remove it a good whack with a 4lb hammer ??? I tried prizing it off with a large flat bladed screw driver but dont want to dent or damage frame and bottom bracket is tightly screwed in holding the whole thing firm will a good whack shift it from the spindle ?

Cheers,

Deano

 

[Wooliferkins]

You might get it off with a car flywheel puller, otherwise this is the tool for the job

 

[Cyclopathic]

A hammer can be used but you risk damaging your chainset. Another method is to simply ride the bike with the retaining bolt taken out. I haven't tried it myself but have heard other people on here saying that it does work. Obviously ride it carefully and keep your eye on it and it should work itself loose.

 

[Crackle]

A hammer can be used but you risk damaging your chainset. Another method is to simply ride the bike with the retaining bolt taken out. I haven't tried it myself but have heard other people on here saying that it does work. Obviously ride it carefully and keep your eye on it and it should work itself loose.

Sounds like a good tip, maybe soak it in some release oil first.

 

[XC26]

Been there many times over the years. As you tighten the puller, you reach that dreaded point where a lot of torque is required and you're not sure whether the crank will come free or the threads will strip. It seems to occur when the crank puller is a little bit of a loose-ish fit in the crank threads. About 4 years ago I bought a BBB crank puller and it's a really snug fit in the crank threads and has (touch wood) not failed yet, even on some pretty tough jobs. It has even removed cranks that had previously had the threads stripped by my older, looser fitting crank puller (now ditched). As far as I know, this is not a thread size issue as both crank pullers I owned claimed to be for 22mm (I think) crank threads.

In the past, with stripped crank threads, I've mostly resorted to the hack saw. I've also once had success with a flat-bladed cold-chisel inserted between bottom bracket and crank, to lever the crank off. Need to have a steel BB cup, space for cold-chisel blade and you mayl end up with a bit of cosmetic damage to inside of the crank, particularly alloy ones. I've also tried the heating (blow lamp) method, which can sometimes work for alloy cranks because, when heated, alloy apparently expands faster than the steel BB axle and so helps to loosen the crank. Obviously, you need to make sure there are no plastic parts involved in the heated area.

 

[mcshroom]

Cranks loosen and eventually fall off if you pedal without a retaining pin. DAMHIKT

 

[Cletus Van Damme]

This happened to me a few weeks ago. I tried removing the retaining bolt and riding it, but it just did not work. I had to resort to a big hammer. I replaced my chainset with a Hollowtech 2 and bought a a fine torque wrench. Maybe the BB will not last as long but at £10 a shot I am not bothered. It also does away with the need for an extractor tool on my best bike, which I am pleased about.

 

[MontyVeda]

my method is just keep riding around the block with no bolt to hold it on and it'll come off eventually... no need for hammers or bearing pullers.

 

[deano69]

Thanks everyone for your views i got it off with a very hefty rubber mallet in the end but crankset is now a right off new one ordered

 

[deano69]

what sort of torque are the retaining nuts on these cranks best set at ?

Any idea's much appreciated,

Deano

 

[RecordAceFromNew]

what sort of torque are the retaining nuts on these cranks best set at ?

Any idea's much appreciated,

Deano

This should answer your question.

 

[XC26]

I destroyed 2 left hand square taper cranks by not tightening the crank bolts enough. They gradually work loose and the soft alloy square taper hole becomes more of a pin cushion shape as the hardened steel BB axle eats into it. The symptoms appear as a loose crank arm which needs continual tightening. Eventually, it bottoms out and can no longer be tightened and is trashed. Having had past problems with stripped threads, I was reluctant to over-tighten the crank bolts. Since then, I've taken to really tightening them up, without a torque wrench. With allen key type crank bolts, I use a 10cm long 8mm allen key inserted into a 20cm piece of metal tubing, giving me a 20cm length lever. I tighten the bolt by leaning, quite heavily, on the extremity of both metal tube and crank. Sometimes, I wonder if I might be over-tightening the bolt. However, the crank-puller always removes them again with ease!