Shimano 105 Shifter TRIM compatiblilty with Tiagra front derailleur

[MaxInc]

The bike has 105 5700 shifters and 105 rear derailleur but the front mech is Tiagra. I read about and noticed the TRIM clicks on the shifter but don't see to have any effects on the front derailleur and I was wondering if the two components are compatible where do I need a 105 front mech to be able to use the TRIM function?

 

[Flying Dodo]

If you're only running a compact, rather than a triple, then the ability to trim by doing a half click may not be necessary. It all depends exactly how much the front mech moves across.

If you're getting smooth shifting without rubbing, across the cassette range, then don't worry about replacing the front mech.

 

[MaxInc]

I do get chain rubbing on the last 2-3 gears on each chain ring but trimming doesn't seem to move the derailleur at all, hence me questioning the compatibility between 105 shifter and Tiagra derailleur.

 

[the_mikey]

Trimming is a feature on 105, so it should work just the same as it does on tiagra, however it may be possible your front gear cable needs re-tensioning or the front derailleur re-indexed or adjusted to reduce the severity of the chain rub problem.

 

[Pikey]

Yes it will work with tiagra, my bike came with 105 shifters and tiagra front mech as stock and the trim worked fine.
As mentioned above, prob a cable tension issue, or limit screws maybe?

 

[MaxInc]

I played with limit screws but never thought about adjusting tension. Will give it a try in the morning, thanks!

 

[MaxInc]

Bingo! Cable tension was too high and the derailleur was not moving under TRIM. Adjusted and it now works brilliantly! Thanks for the advice, this should decrease the nmber of shifts significantly!