# Shimano Ultegra 6800 1x11 with 11-40 cassette?



## The_Mickstar (Apr 22, 2008)

I currently have an Ultegra 6800 1x11 setup on my gravel bike. I'm running a short cage (SS) rear derailleur and 11-32 cassette. (I realize the SS rear derailleur is only supposed to go up to a 28t cog, but it works fine. Apparently, the derailleur hanger on my frame is long enough.)

I would like to move to an 11-40 cassette for easier climbing when loaded (bikepacking). I believe I can accomplish this with a Wolftooth Roadlink (and possibly a mid cage GS derailleur). 

Can I use a Shimano XT M8000 (or SLX M7000) cassette with the otherwise road grouppo (i.e. is the cog spacing the same between Shimano 11sp road & mtb)? 

Will I need a spacer behind the cassette on my road 11sp hub? If so, what size?

Thanks.


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## satanas (Feb 12, 2005)

In my experience, Roadlink = crap shifting, so best avoided.

Re cage length: unless the top jockey wheel is offset differently/better on the long cage version, you might well be okay with the short cage. As the chain becomes tighter on the larger cogs it pulls the top jockey wheel down and away from the large cogs; clearance there is likely to be the limiting factor.

Cassette spacing is the same for road and MTB, but you'll need a 1.8mm spacer to make up the difference in cassette body length.

If your road RD won't work it might be worth using an M8000/M7000 RD with a Wolftooth Tanpan. That way you could use just about any cassette up to at least 46T, and have a clutch, so it should be quieter too.

FWIW, I've used a 5800GS with a 48x32 and 11-36 (stock on a Specialized Sequoia Elite), with an 11-40 (just works, with the slightly-too-short chain from the 11-36), and also tried it with 11-42 plus Roadlink (terrible shifting everywhere); 11-40 plus Roadlink also gave crap shifting - much better without it.

You may also find this interesting:

Tinkering 101: Shifting big gears with Shimano Dura-Ace 9100/9150 & Ultegra 8000/8050 Derailleurs - Gravel Cyclist: The Gravel Cycling Experience


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## SteveF (Mar 5, 2004)

I find the roadlink to work fine with an 11-36 10 speed cassette, 36-46 cranks. Worth a try and they don't cost much.


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## 749800 (Jul 14, 2013)

I have a mid-cage Ultegra (Di2) working with both a SRAM 11-36T cassette and an Ultegra 11-34. With a 46/30T up front, I get low gearing compatible with Di2. The only thing I had to do was crank on the B-screw. Shifts fine.


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