Originally Posted by bikerdave
Problem with one of my cranks coming loose.Had them on the bike now for about 3 years and been fine, but one just keeps coming loose.4 year old chorus chainset.Ive took out the bolt and cleaned it, tightened it up again...even put Loctite on it, but after a while still comes loose.The threads seem fine and dont appear to be worn?confused
My bet is that your crank arm spindle hole has been hosed. Once they come loose, the hard bottom bracket spindle wallows out the softer aluminum crankarm and they tend not to want to stay in place after that. That's why I always use a torque wrench when tightening crank arms. My experience has been that many people, when left to their own devices, tend to undertorque crank arms.