Front shifting problem.

[Garry A]

Hello, I have a problem with my front derailleur shifting. I have a Sora compact double on my 2015 Giant defy and it won't stay on the top setting on the big ring, it keeps popping down to the trim setting. I replaced the cables but this didn't help, sprayed gt 85 into the shifter but that made no difference. The front derailleur has been cleaned and lubed. It's all been set up according to the Park tools video. The shifter goes through all the settings until cable tension is added then it gives up. Interestingly if I press on the derailleur cable arm when shifting up and hold it for a second, it stays in the top position until I touch the shifter lever.
Is my shifter just done? I wouldn't say I've done super high mileage.
Thanks, Garry.

 

[HLaB]

Might be the cable fraying in side the hood ?

 

[Garry A]

Just replaced the cable inner and outer, did it before and after.

 

[raleighnut]

Try moving the high limit screw a fraction 1/4-1/2 a turn out.

 

[Garry A]

Turned it out enough to throw the chain. Had the chain off, limit screw all the way out. No difference. Even lowering cable tension to a minimum, still pops down to upper trim. Think something in the shifter must be rounded off.

 

[Garry A]

I've set the derailleur so that it doesn't rub in any gears at the upper trim. Just annoying that it does this.

 

[Cycleops]

Sounds like it could be the shifter. Unclam the cable, hold it under tension and operate the shifter. Is it pulling the cable?

 

[Garry A]

Sounds like it could be the shifter. Unclam the cable, hold it under tension and operate the shifter. Is it pulling the cable?

It is pulling the cable. It does move the derailleur but when moving to the big ring it automatically pops down to the upper trim position.
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