Removing Stuck Cranks - Advice Please

[2wheelsgeth]

Hi All,

Could really do with some advice about how to remove stuck cranks on my tired old early 90s Diamond Back Topanga MTB. I need to replace the bearings in the BB (which I think is a three piece loose bearing type - Shimano Exage 300LX if that helps), but the cranks are stuck firmly to the square taper. If anyone has any useful tips to remove these without causing any damage, I'd be very grateful.

As the more experienced of you will have no doubt noticed, I'm a bit of a novice to this, having taken cycling back up in the last few months, so I might struggle with the correct terminology - apologies!

Ta...

 

[tyred]

I assume you have tried with the correct removal tool?

If it won't work or the threads are knackered, unscrew the bolts which hold them on the taper but leave them loose with just a few threads still holding and go for a ride.

 

[smokeysmoo]

Without wishing to state the obvious, use a CRANK PULLER

It's the only safe way to ensure you don't damage anything, (as long as you don't cross thread it screwing it in)

There is an old school method of loosening the crank bolts and riding around the block until the arms loosen, but I've never tried it, (I have a crank puller), and I wouldn't personally advise it. If you don't want to invest in the right tool nip to your LBS, they should be prepared to crack your cranks, (not literally) for a nominal fee.

[EDIT] slight cross with above post

 

[2wheelsgeth]

Thanks very much for this - will give it a go and see what happens!

 

[smokeysmoo]

Thanks very much for this - will give it a go and see what happens!

That sounds like your giving the loosen the bolts and go for a ride method a go.

If so, be very careful, keep checking the crank arms, if they loosen and you keep peddling you could damage the square tapered hole which could result in them constantly working loose when you've rebuilt it.

This is one of those times when there is no solid substitute for the correct tool

 

[2wheelsgeth]

That sounds like your giving the loosen the bolts and go for a ride method a go.

If so, be very careful, keep checking the crank arms, if they loosen and you keep peddling you could damage the square tapered hole which could result in them constantly working loose when you've rebuilt it.

This is one of those times when there is no solid substitute for the correct tool

No, I think I'll have a go with the crank puller first. Wasn't even aware such a thing existed until you mentioned it (so much to learn). A trip to one of my local LBSs beckons. At least I know what I'm asking for now!

 

[smokeysmoo]

No, I think I'll have a go with the crank puller first. Wasn't even aware such a thing existed until you mentioned it (so much to learn). A trip to one of my local LBSs beckons. At least I know what I'm asking for now!

Spot on The link I posted earlier was to a Park Tools crank puller, cheaper ones are available, but if you do buy one it is worth buying a decent one because if something goes wrong when using one it can cause a fair bit of damage that could mean needed new cranks!

Don't let that put you off, they are easy to use, just be careful and make sure the threads in the cranks are spotless, screw in nice and gently and just take your time.

If you get your LBS to get them off you don't need any special tool to re-fit them, just a socket set to re-tighten the bolts.

 

[ohnovino]

Don't let that put you off, they are easy to use, just be careful and make sure the threads in the cranks are spotless, screw in nice and gently and just take your time.

+1 to that. It's really easy to cross-thread, so don't force the tool into the crank.

Even with the tool you might find getting the cranks off takes a little bit of brute force, especially if they've been on for a long time. I use my crank tool with a very long wrench, and usually have to give a sharp tap on the end of the wrench with a lump hammer just to get it turning.

 

[2wheelsgeth]

Brilliant - great advice everyone. Much appreciated - I feel better equipped and less terrified now, whch can only be a good thing!

 

[Panter]

Good stuff

And, don't feel bad about it, I spent ages trying to beat my cranks off with a hammer recently until resorting to Google and discovering what that funny looking tool in my bike toolbox was...

 

[2wheelsgeth]

Good stuff

And, don't feel bad about it, I spent ages trying to beat my cranks off with a hammer recently until resorting to Google and discovering what that funny looking tool in my bike toolbox was...

That definitely makes me feel less of a buffoon! Thanks everyone

 

[Night Train]

I have a couple of this type of tool.

Don't know how I ended up buying two but they have been spot on for removing the cranks.
The silver end is a socket for the retaining nut/bolt and the black end is the extracter. A much more conpact tool then the type with the handle and it fits the same 16mm spanner for the axle nuts.

If it is a really stubbon crank I wind up a bit of pressure on the tool and then strike the end of it with a hammer to shock the crank off the spindle.

 

[2wheelsgeth]

I have a couple of this type of tool.

Don't know how I ended up buying two but they have been spot on for removing the cranks.
The silver end is a socket for the retaining nut/bolt and the black end is the extracter. A much more conpact tool then the type with the handle and it fits the same 16mm spanner for the axle nuts.

If it is a really stubbon crank I wind up a bit of pressure on the tool and then strike the end of it with a hammer to shock the crank off the spindle.

That looks good. Any idea who makes them?

 

[MontyVeda]

That looks good. Any idea who makes them?

have a look at the Ice Tools... they do the job without the expense of Park tools. My last one was about £6 off Ebay.. but I can seldom find it so i do tend to use the 'loosen bolts a tad and ride round the block.. as soon as they come loose, push the bike home' method.

 

[smokeysmoo]

That looks good. Any idea who makes them?

Check THIS out