Bicycle Mechanics - My crankpuller stripped my threads. What do I do?

While trying to pull my square tapered crank off my mtb (2005 Haro V1) the crankpuller stripped the threads off the drive side. I tried reinserting it deeper and the same continued? I have a replacement crankset already. What do I do to get the old crank out?

Were you only hand-tightening the puller into the cranks? You really have to get the puller installed tightly into the crankarm before you tried to remove it.

You may have to use a 2-jaw pulley puller. They can be found at most autoparts stores. I can see in theory how it would work fine, but I don't know if the sizes available will work for the cranks as I have never tried it myself.

This happened to me on an old crankset on my Schwinn World sport. I loosened the tightening screw/nut and rode it on short trips. A couple of days later it cam free. I got home the rest of the way by pedaling on one side only.

Either:

1. You didn't thread the outer ring completely into the crank's threads
2. You left the screw press center bolt extended too far so the outer ring wouldn't thread in completely
3. You left a washer under the crank fixing bolt in place
4. The crank's threads were badly corroded and weak

To remove the damaged crank, either a gear puller or riding it with the fixing bolt threaded in just far enough to keep it from falling off completely will do.

5. You used the wrong sized puller.

Since the crank you're trying to remove is now garbage, maybe you could hacksaw it off.

Cut into it the same way my crankarm cracked one day:

http://i845.photobucket.com/albums/ab15/dunncrew/CrackedCrank6.jpg

The easy way is to loosen the crank bolt to about a turn looser than you can turn it by hand. Then, get on the bike and ride it. The crank will come loose quickly.

Every so often stop and wiggle it to see if it is loose.

In some cases there is an almost invisible thin, plastic, washer between the first bolt you unscrew - and where you then screw-in the CP. If you don't check for this - you can strip either your crank, your CP, or both.

If not the case here - keep that in mind for the next disaster.

Take the non drive side off, then take the whole bottom bracket apart, put it in vise then drive the axle through with a punch. Or just loosen the bolt and ride it, it'll fall off.

+1 My guess is that the washer is still in the crank.

In some cases there is an almost invisible thin, plastic, washer between the first bolt you unscrew - and where you then screw-in the CP. If you don't check for this - you can strip either your crank, your CP, or both.
The washers I've seen have all been metal and they WILL ruin your crank if you don't remove them before threading in the puller.

I suggest taking the crank bolt all the way out an riding in circles in a parking lot. After I striped a crank (stupid washer) This solved it for me in about 15 minutes. It's also a good illustration as to why you should always properly torque crank bolts.