Crank removal

[ian slater]

Hi everyone
I am fitting a conversion kit to a specialized hardrock, came to fit the pas sensor and tried to remove the crank.Have a crank extractor which outer part screwed in fine then screwed inner part in but it just bottomed out.Looked through the crank but hollow. Do you have to have a different tool to extract crank on this particular bike.
Thank you

 

[Sturmey]

I am assuming that your bike has the square taper type bottom bracket/crank. Some crank extractors come with a cap as shown below but I have seen the caps a little too large for the square hole. I always use a small m6 bolt with the head filed a little smaller. But a nail with large enough head or washer with a small hole should do the trick. It should be just big enough to go flat through the square hole in the crank.

 

[ian slater]

Evening Sturmey
I'm pretty sure i know what you mean, so just need to put something inside for the centre part of crank extractor to push against when tightening it and this will then release the crank
Thanks

 

[saneagle]

Hi everyone
I am fitting a conversion kit to a specialized hardrock, came to fit the pas sensor and tried to remove the crank.Have a crank extractor which outer part screwed in fine then screwed inner part in but it just bottomed out.Looked through the crank but hollow. Do you have to have a different tool to extract crank on this particular bike.
Thank you

Yes, there are special ones for that, which have a larger part that presses against the end of the crank.

I've done it by inserting a washer or two into the hole, but it really needs to be a thick strong washer, otherwise it'll bend.

 

[ian slater]

Hi Saneagle
On hand again to help me,thank you once again
Regards
Ian

 

[Raboa]

I have never used the company in the lists but it gives you an idea.

Park Tool CCP-22 - Cotterless Crank Puller

The benchmark crank puller of the cycle industry for over 25 years The CCP-2.2 uses a long comfortable handle and extra fine thread that provides the leverage required to remove even the tightest cranks Unique floating-tip design has been updated over the CCP-2 and ensures even smoother...

www.bikeparts.co.uk

Park Tool CWP-7 - Crank Wrench and Puller

The CWP-7 is a compact crank puller with a built-in 8mm hex for removing crank bolts Includes two rotating tips (11.3 mm and 16.3 mm) so it can be used to remove splined Octalink and ISIS Drive crank arms, as well as square-holed crank arms A must have multi-fit crank puller for the home...

www.bikeparts.co.uk

 

[ian slater]

Morning Raboa
Thanks for sending these,can you remove crank arms individually only i want to remove non drive one just to fit a pas
Regards
Ian

 

[Waspy]

Be careful, it's easy to strip threads on this job.

 

[Raboa]

Yes, you can remove each arm individual.

When I remove my crank arms, I give the end of the bottom bracket shaft (square bit) and the square hole in the middle of the crank a quick wipe with isoprayal acholol. It's worth removing both arms at once for this reason.

Some of the crank extractors (2nd picture in message) have less threads on them. I found the Park one to be better as it has more threads, both of the Park tools are good.

 

[soundwave]

 

[volt x]

Rather than start a new thread , I'll come in here and hope for a solution to my issue. I can remove the crank arm on the left side, but on the drive side it's not moving at all. The removal tool is okay, one part black the other chrome and using a spanner is just wearing the nut edges away.

The bike is 7 years old and has never had the drive crank removed. Assuming I need a new or better removal tool, how much force would be reasonable to use. The bearings are making a horrible sound hence the reason for trying to remove the crank. It's square tapered BTW.

 

[saneagle]

Rather than start a new thread , I'll come in here and hope for a solution to my issue. I can remove the crank arm on the left side, but on the drive side it's not moving at all. The removal tool is okay, one part black the other chrome and using a spanner is just wearing the nut edges away.

The bike is 7 years old and has never had the drive crank removed. Assuming I need a new or better removal tool, how much force would be reasonable to use. The bearings are making a horrible sound hence the reason for trying to remove the crank. It's square tapered BTW.

What nut edges are being worn away? Normally, no nuts are involved.

 

[volt x]

What nut edges are being worn away? Normally, no nuts are involved.

The removal tool itself, I can't think of what you might call the part where a spanner would be use, let's say it looks like a nut a behaves like one. This is the chrome part , the one that removes the crank arm. Plus I've just realised it's not the drive side that is the issue. It's the left side , I've decided to have another go at removal. Only to find my mistake

 

[Cadence]

Tighten the tool as much as you can without rounding the flats on it, then give the end a single hefty blow with a decent sized mallet or hammer. This usually loosens the square taper.
Just make absolutely sure you have removed the bolt or nut from inside the crank hole first. Seems obvious but I forgot once and stripped the thread in the crank arm!

 

[volt x]

Okay strike that, I've just managed to remove both sides. I've been using adjustable wrenches, the first one I used was a bit not right. So I used the mother of all adjustables, a bigger one and not a problem at all. It's the fear of doing damage that holds some of us back. So feel the fear and do it.

 

[matthewslack]

If it is like this...



...isn't the end a 1/2" square socket drive?

In which case use your longest, strongest Tommy bar and if necessary a piece of scaffold pole to lengthen it.

Try @Cadence's tip as well, and you have probably already made sure the black bit is fully engaged by backing out the chrome bit before screwing it in, and the retaining bolt is out already.

A long bar should do the job.

 

[Sparksandbangs]

It's the fear of doing damage that holds some of us back. So feel the fear and do it.

Until you strip the threads out the crank arm. Then swear a lot.

 

[saneagle]

...isn't the end a 1/2" square socket drive?

It's a hexagon to remove the nut on the end of the crank if you have one.

 

[volt x]

I'm trying to remove the bottom crank and this is turning out to be a problem. Drive side is turn right to remove, left to tighten. Non drive the opposite. Is this correct, if it is then Huston we have a problem. I seem to be chewing the ring nut on the non drive side. Awaiting reply before I do anymore damage.

 

[Sparksandbangs]

I'm trying to remove the bottom crank and this is turning out to be a problem. Drive side is turn right to remove, left to tighten. Non drive the opposite. Is this correct, if it is then Huston we have a problem. I seem to be chewing the ring nut on the non drive side. Awaiting reply before I do anymore damage.

If you are talking about removing the bottom bracket then if it has been there for a long time then it will be almost impossible to get any purchase with the standard tool. Every time that you apply any pressure the tool will slip off and chew the ring. Trick is to soak the thing in penetrating oil and have an adaptor that clamps onto the square taper. This ensures any pressure will be exerted onto the threads and no sideways movement.
You can make your own adaptor with an M8 fine thread set screw (probably, can't remember)and a couple of washers or buy one.

Left-hand side is a standard thread, right-hand side is reverse thread. Left side needs to be slackened off first.