How to Easily Remove a Crank from Your Mountain Bike
To take a crank off a mountain bike, first remove the pedals using a pedal wrench. Then, use a crank puller tool to remove the crank arm from the bottom bracket spindle. Insert the tool into the crank arm and tighten it until the crank arm pops off. Repeat the process on the other side if necessary. Be sure to follow any specific instructions for your particular crank and bottom bracket type to avoid damaging the bike.