Originally Posted by Deanster04

I rebuilt a set of wheels for a friend who had a lot of miles on the wheel. There was a significant amount of wear where the spokes rubbed together. In this case about 20% of the diameter on both spokes. The made a pinging sound in the way you described. New spokes and rims fixed the problem. There was about 30K miles on the wheels. When is showed this to a couple of professional builders they had seen the same effect on old wheel sets but, this was about the worst they had ever seen. Check it out by grabbing 2 spokes and squeezing them together and see if they have abraded.