Crooked derailleur hanger vs bent hanger: why does everyone mix these up?
I keep seeing people at the shop saying their derailleur hanger is bent when it's actually just crooked from a loose bolt or bad alignment at the frame dropouts. I had this guy come in last Tuesday with a brand new Trek he crashed once, swore the hanger was bent. I threw it on the alignment tool and it was dead straight, but the bolt was barely finger tight. Tightened it up, shifted perfect. On the flip side, I've also fixed bikes where the hanger was actually bent 3mm and people swore it was fine because they didn't see a bend. Which camp are you in? Do you always check with a gauge or just eyeball it?