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I have a new bike (about a month old). It has Shimano 105 2x11 group set. The shifting works fine but I have noticed something odd on the front derailleur shifting.

I am in the big cog at the front. I shift to the small cog by pushing the lever as far inwards as it will go. It shifts nicely to the small cog.

However, I can then push the lever inwards some more and the front derailleur will “shift” a bit further. This doesn’t affect the gears at all as far as I can tell.

I have put the bike on a stand and done this whilst watching the front mech closely and sure enough, I shift to the small cog (really making sure to push the lever all the way across) and I can see the mech move. But then, I push the lever again and it shifts a bit more and the moves a My partner has almost the same bike with same group set and her’s does the same thing.

Hopefully I explained that in a way that makes sense.

Is it normal?

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Ben, congratulations on your new bike!

Yes the behavior is normal. The large cog should have a similar setting, i.e. if you don't shift all the way to the small ring, but just click gently, it should move into an intermediate position as well.

This is called "trimming" and is important to allow the chain to access all rear cogs without scratching on the derailleur. The trim position which you access with the extra click is suitable if you are running a lower gear at the back.

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  • I was going to suggest an extract from the ST R7000 user's manual but I thought that it was more confusing! – Swifty Apr 4 at 8:07
  • Thanks! Knowing what to search for led me to some stuff. When riding, would I ever shift all the way down to that “low trim”? Or is it just for adjusting the derailleur? – Ben Apr 4 at 9:42
  • If you have the opportunity to watch a Di2 front derailleur in action you'll notice that it does this kind of trimming adjustments while the RD is shifting. – Carel Apr 4 at 11:38
  • @Ben when on the small ring and shifting towards smaller cogs you'll trim the FD towards the right. Similarly when on the big ring and shifting from the smallest cog towards bigger ones you'll let the FD move slightly to the left. The opposite applies in both cases. – Carel Apr 4 at 11:44
  • @Carel the thing is that the trim position for the big rong ks between the big and small ring. But the trim position for the small ring is not between the two rings (it’s further inboard of the small ring). So when on the big ring if I do a full shift to the small ring, after the chain has shifted, I can then do another trim shift so the derailleur moves even further inboard. Would I ever need to use this when riding? I would have thought shifting normally to the smaller ring would be sufficient to use with the biggest cog at the rear? – Ben Apr 4 at 20:16

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