Originally Posted by DieselDan
WD-40 has only two good uses on a bike:
Freeing up old Shimano brifters.
Shining up a frame.
+1 on freeing up old Shimano brifters. I almost never use WD-40, with the exception noted by DieselDan. I've been able to bring back 3 poorly operating/frozen brifters and two trigger shifters using WD-40. But after cleaning them, I follow-up with a spray, chain lubricant.