A guy at the Fort Worth swap meet sold me a bent rear derailleur hanger for $3 and it fixed my shifting
I spent two hours trying to index a 10 speed on a customer's bike and could not get the top two cogs to stop skipping, then a vendor at the Fort Worth swap meet pulled out a hanger gauge and showed me the dropout was off by about 4mm. I bought his alignment tool on the spot for $65 and now I check every frame that comes in the stand before I touch the cables. How many of you actually gauge the hanger first, or do you just chase the barrel adjuster like I did?