Took me 2 days to chase down a creak that turned out to be 1 loose chainring bolt
A customer brought in a '93 Rockhopper with a creak that I guessed would take 20 minutes, but it kept coming back after every test ride around the block in Boise. I swapped the bottom bracket, greased the seatpost, even pulled the headset apart, and it wasn't until I put a torque wrench on the chainring bolts that I realized one was just barely loose. How do you all track down phantom noises without just firing the parts cannon at it?
Grab the bike and squeeze the cranks side to side while you rock it, then drip a little oil on each chainring bolt one at a time. The oil trick is the fast way, the creak stops when you hit the guilty one. Saves you from throwing parts at it for two days like the rest of us did.