Help! Totally messed up the rear derailleur…

[Deleted member 121159]

Hello all

I messed up the derailleur set up by playing with the B screw and derailleur hanger. Now it’s stuck in this position and shifts only between a few gears. What have I done?! Any advice would be appreciated. B screw is screwed in all the way yet the derailleur is almost sticking to the chainstay

 

[Ajax Bay]

First suggestion: remove derailleur, have the b screw half in/out and refit ensure b screw meets the correct detent.

 

[Deleted member 121159]

Thanks for the response! I'll try that.

I've also noticed that the hanger (not the actual hanger that attaches to the frame, but one that is between that and the derailleur) looks different from in this photo. Mine looks more vertical than below. Could that also be causing an issue?

 

[Grant Fondo]

Thanks for the response! I'll try that.

I've also noticed that the hanger (not the actual hanger that attaches to the frame, but one that is between that and the derailleur) looks different from in this photo. Mine looks more vertical than below. Could that also be causing an issue?

View attachment 659801

Think you have spotted it, here's mine, almost horizontal.

 

[Deleted member 121159]

I've fixed it now (although the indexing is horribly off so I'll have to work on that tomorrow). The link between derailleur and hanger was indeed the culprit. I'm not sure how I did it but it didn't sit properly previously so pushed the derailleur forward to the chainstay.

 

[I like Skol]

We've been here before. I will find the thread in question because it's easier than explaining it all again.....

 

[I like Skol]

Found it.

https://www.cyclechat.net/threads/rear-derailleur-installation-issue.251766/#post-5694778

 

[Deleted member 121159]

Found it.

https://www.cyclechat.net/threads/rear-derailleur-installation-issue.251766/#post-5694778

Yep, that's exactly it. In my case, I hadn't even removed the original chain and cable which were working fine before, so it completely baffled me when they suddenly seemed too short. The mech indeed has to sit properly against a hard-to-see notch in the hanger.

 

[Grant Fondo]

Yep, that's exactly it. In my case, I hadn't even removed the original chain and cable which were working fine before, so it completely baffled me when they suddenly seemed too short. The mech indeed has to sit properly against a hard-to-see notch in the hanger.

Glad its sorted