Might seem silly and I might get shot down for saying this but you know how quickly your crank arms seem to come loose if the bolt ain't on tight, well try that, ride around for a bit with the crank bolt un-done and see if the spinning / body weight helps loosen it??
Might seem silly and I might get shot down for saying this but you know how quickly your crank arms seem to come loose if the bolt ain't on tight, well try that, ride around for a bit with the crank bolt un-done and see if the spinning / body weight helps loosen it??
Just a thought