Originally Posted by Leigh30
The only way I can see them loosening is due to the fact that you can't get anywhere near the same torque on the bolt as with a standard bolt head...that is, with a standard short Allen wrench - one with a longer handle may be different, but nevertheless there is no reason why they should undo if they done up nice and tight...
I use the same 3/8" drive ratchet, but with the appropriate bit. Sometimes I even use my torque wrench. You can't properly torque a crank bolt with a little allen key.