Tech TipsDrivetrain

How to Save a Bent Mech Hanger

Shifting suddenly feels off? How to spot a bent mech hanger and straighten it accurately with an alignment gauge before it wrecks your drivetrain.

Rear derailleur and cassette on a bicycle drivetrain, illustrating where a bent mech hanger is diagnosed

It’s a familiar tale; you get in from a great ride, the sun was shining, the wind was always on your back. In his excitement to see you again the beloved family dog knocks your bike over. No big deal, he’s always a good boy so you let it go.

Next ride, you set out and the gears aren’t quite performing right. It’s not that they’re up-shifting or down-shifting badly, it’s just everything seems a bit off. You take a look down and realize your rear mech is crooked, and immediately wonder if the dog is such a good boy after all.

A bent mech hanger is a relatively common problem, either after a crash or even after something benign like poor storage. The hangers are built to be weaker than the frame so as to sacrifice themselves in the event of any trauma. At best it usually results in sloppy shifting, but in extreme cases it can result in your derailleur getting a lot more friendly with the spokes in your rear wheel.

Fortunately most are easily replaceable, but in current times part shortages may mean a long wait. Do not despair, for you may be able to bring them back from the dead...

The best way and the way we would strongly guide you towards is by using a Hanger Genie. This tool is made for the job and will work on bikes with wheel sizes 20" thru 29+ - it provides leverage and accuracy. If this doesn't solve the problem then it's new hanger time.

Hanger Genie being put to work.

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