Hi fietsbob,

I don't know if you were commenting on me or not. If not just ignore this.

I have a full 11 speed Ultegra system. My comment about adding links is because of the chain wrap that my bike now has. The stock Ultegra 6800 chain has 116, going off memory here could be wrong. The problem is when I went to a 40T rear cog my chain wrap went from 82 (32/50) total teeth to 90 (40/50) total teeth. What this meant in my case if I'd accidentally shift to large/large I would rip the derailleur apart. Rather than risking that I "added" links to the chain and am running a 119/120 link chain, never counted so not positive. If I shift into large/large that cage on the derailleur is pull all the way forward but it wont ripe it apart.
Now the only time I ever shift into this combination is to perform the front derailleur trim as required by the Di2 system. I never ride this combination as I'm pretty sure that it would damage the derailleur in a hurry since it's pull all the way forward.

I ride 34 front in 40 thru 17/15 and 50 front in 31-11. 34/15 is kind of pushing and I do have some chain sag so don't normally ride that combination but could if I had to. What this does is keep my total tooth count in the 51-81 tooth count range which is still in the stock tooth count range for an Ultegra GS derailleur. Stock tooth count range is 46-82 the reason for 51 is because of the links that I've added to the chain.

For those interested my shifting pattern pretty much goes like this 34-40,35,31,27,24,21 than to 50-31,27,21,19,17,15,13,11 (this is without the Schlumpf.)

Hope this clear up any confusion.

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