Can't get the crank off
 

I'm trying to take the crank off an old bike and put it on a newer bike. The problem is, I can't seem to get it off no matter what I do. One side is off, but the side with the crain rings is the one stuck. I have a crank puller, but the threads are damamged/stripped inside the crank arm. It will not thread on enough to bite. I've tried lightly tapping the back side of the crank to get it off. I've tried using WD40 to loosen it up, but no luck. Any suggestions?

Of the many different options, try using an automotive gear puller.

I had a similar problem on the non-drive side. I removed the bottom bracket's adjustable cup and pulled out the spindle with the stuck crank arm. Next, I put the crank and spindle in an arbor press and pressed out the spindle. It didn't require a great deal of force and did no damage to the crank and spindle.

http://lh3.ggpht.com/_TIeBxBH6dXI/TT...rbor_press.jpg

Your situation is more difficult because the fixed cup is harder to remove, but it's certainly possible.

I unfortunately had to do just this last summer. however I could not summon up the courage to return the once used gear puller to Harbor freight.

if there's a good industrial hardware store in your area you can buy a pair of Jacobs Chuck removal wedges. They pretty cheap and have a shallow taper so they don't require much force. When used in pairs between the back of the arm and bottom bracket, they'll gently and evenly push the crank off with zero damage to either.

In fact they'll work so well that you'll feel confident enough to continue using the stripped crank with these as the remover of choice.

Once I had the problem and read someone's suggestion to carefully ride the bike until it comes off. Of course I had to put the other crank back on but riding it around the neighborhood for a while loosened it enough to come off.

A perfect example of turning Murphy's Law to advantage, and it works pretty well. If you want to try this method replace the crank bole then back it out about 1 turn. this will let you hear and feel when the crank pops free, but protect your ankles from any dire consequences. BTW- climbing steep hills in a high gear works best.

Funny, that's where I bought mine.