Is there anyone who has had luck using a 2 or 3 arm crank puller to remove the crank arms off a tapered bottom bracket?
While Chris Dottavi mentionned that jaw pullers are not meant to remove crank arms, they can definitively used for that, although you might want to think bit before doing so.
I do work in a community bike workshop, where we have a lot of people comming with bicycles that can be quite old or in bad shape. It is therefore not always possible to use the usual crank puller. Therefore, we sometimes have to do otherwise. For the sake of completeness, here is the list of things I have done, in order of preference.
For recent (squared) bottom brackets:
- try with a regular crank puller, if you have the right one (check the standards, in particular if you have an odd bike).
- try with a jaw puller. Depending on the jaw puller and the shape of the star of the right crank, it might be more or less easy to grab it (for instance, if you have a "5 leg" spider to hold the crankset, it might be difficult to place the tool if you use a 2 jaws puller). Also, depending on the end of the screw of the puller, you might want to keep the crank screw (just unscrew it for a few turn). Indeed, if the screw of the puller is to small, it can destroy the threading of the axle (happens almost never, but not never). The main advantage of that technique is that, if you are careful, it most likely preserves the crank (assuming you are interested in keeping the crank, e.g. if you did not have the right crank puller).
- unscrew the crank screw, and go for a ride. I rarely do that, since it might require some time (and, at the workshop, we can not really say: "take a ride and come back"), but it most likely work, often quickly. Some drawbacks: if you have aluminum cranks (most likely on modern bikes), you do not want to ride with the loosen crank: the squared shape hole will quickly not be that square anymore (once again, if you intend to reuse the crank).
- with a torch, you can warm the crank, so that it expands (faster than the axle). I've done that only once, so I can not really tell some advices
- Finally, if, with all that, the crank is still tight, you can cut it with an angle grinder. Take care of where you cut, as you do not want to cut the axle or the frame. I usually do three cuts. This is really last resort: the crank is (of course) not reusable, but it is also quite likely that the axle get damaged too, sometimes the cup too. While wuite extreme, this is sometime the only way to recover some frames.
For older (cotter) axles/cranks: You should not have any problem with those, once the cotter is removed. If you have, you can hit (gently) the crank with a hammer, or use a jaw puller.