Can you assist please,
how can I check if straight the rear hanger on the rear mech of my bike, it has a steel frame therefore not replaceable, bike is a Mercian and the hanger is chromed.
Do I need special tool status.
Thank you Tom
derailleur securing situation
Re: derailleur securing situation
Clamp a ruler to it?
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rogerzilla
- Posts: 3124
- Joined: 9 Jun 2008, 8:06pm
Re: derailleur securing situation
Use a long steel rule or similar straight edge and sight against the seat tube. Also check for skew by measuring the distance between a straight edge and the RH BB shell face. For 130mm spacing and a 68mm shell this should be 31mm plus the width of the hanger, if you hold the rule against the outer face of the hanger. Even a tiny skew will.put this right out.
I am assuming the front triangle is good and the hanger is flush with the RH dropout. If you have weirdly-sculpted dropouts this may be difficult.
You can straighten a steel hanger with a large adjustable spanner but go in small steps so you never over-correct and need to bend it back.
I straightened a very bent Kona Cinder Cone hanger this way and the gears shift impeccably now.
I am assuming the front triangle is good and the hanger is flush with the RH dropout. If you have weirdly-sculpted dropouts this may be difficult.
You can straighten a steel hanger with a large adjustable spanner but go in small steps so you never over-correct and need to bend it back.
I straightened a very bent Kona Cinder Cone hanger this way and the gears shift impeccably now.