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I have a Specialized Hardrock I'm trying to remove the crankset and bottom bracket from. It's a square taper crank and I do have a Parktool CWP-7 however I have yet to understand how to use it exactly for this project. I tried watching the Parktool help-me-fix-it guide and YouTube but to no avail. Any pointers would be appreciated

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Normally a square taper would have two separate crank arms that need to be removed first. That means using a crank puller to force the cranks off the tapers that are integral to the bottom-bracket axle.

Exactly how you do that depends on the crank arm. Some have internal threads for the tool to mate with. Other cranks have a "self extractor" function where you do something with a bolt that applies pressure - nifty but variable.

Tools: You need a big spanner/adjustable wrench. A 250mm/10 inch is ideal, 6 inch is getting too small.
A 14mm socket and suitable socket driver are required to undo the bolt that holds the crank-arm to the BB axle.

Your CWP-7 looks something like this:

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Start by popping any plastic covers off the cranks that look like weather seals. Inside you should see a female thread which has an ID to match the OD visible on the left-side of the tool. Remove the bolt from inside this area, it will be standard Right-hand thread. If your BB/crank use something different, it might need a hex driver.

Extend the crank puller tool by unscrewing the right-hand end (as pictured) from the central part. You're trying to get the pusher (extreme left end) to pull back into the body of the tool.

Lubricate this thread well if the tool is new, it takes all the force soon. Both the outer visible thread and the smaller one inside the tool need good lubrication with grease or medium oil. Light oil is better than nothing.

Once the pusher is flush with the end, you can thread the big thread into the side of your crank. Do note that it is very easy to cross thread and damage things - the tool will be completely parallel to the axle centerline, and not the crank arm.

The puller should thread in at least 6 full turns. Nip it up with the spanner.

Then start threading in the core of the tool. That will press the pusher plate against the end of the BB axle. Tighten it firmly, and then relax for a moment. The pressure will force the crank arm off the axle/spindle taper. Normally this is a gradual release of pressure, but occasionally it can be stuck and then let-go with a bang. This is unusual though.

Once the crank arm is loose it will just come off the bike in your hand and the puller will be threaded in. Simply use the spanner on the big external hex to remove the tool, and it should look as-pictured with the pusher plate poking out again.

The Right-hand side crank will bring the spider and chainrings with it and may hang up on the chain.


After that, the ends of the BB are exposed for removal. You may need a specific spline tool, or you might need a big big spanner, or some odd-ball cycling-specific spanners. A photo of each side would help here.

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