DAE lose a whole Saturday to a rear derailleur hanger that was bent 2mm and nobody noticed?
Had a customer drop off a bike at the shop on Grand Ave complaining about ghost shifting in the middle cogs, and my first three guesses (cable tension, worn cassette, sticky shifter) were all wrong. I finally pulled out the hanger gauge around 4pm and sure enough, it was bent just 2mm, which was enough to throw off the whole range. I straightened it with the Park tool in about 90 seconds, and the shifting snapped back to clean. Now I check the hanger first on every tune-up before I touch a cable, and it saves me so much time. How many of you made this same mistake early on?