Ultegra 6700 / 6800 rear mech compatibilty

Has anyone successfully got an Ultegra 6800 11 speed rear mech with 6700 10 speed shifters?

I’ve tried this morning but can’t achieve perfect shifting in every gear; I assumed that the shifter controls the amount that the mech moves and therefore expected an 11 speed mech to be fine paired with a 10 speed shifter.

Has shimano changed the actuation ratio on the 11 speed mechs?

Leverage ratio at the mech could have changed between the groups.

i believe the cable pull is different on shimano 11 speed road groups
so it’s probably not going to work right ….

second question down … http://velonews.competitor.com/2014/07/bikes-and-tech/technical-faq/technical-faq-1011-speed-compatibility_337803

I have done it but it isn’t perfect. I ran 105 5700 shifters with a 6800 rear mech. Shifting worked but there was always hesitation to shift into either the big cog or small cog depending on the adjustment. If you want perfect shifting then the combo isn’t compatible. On a weird note using an MTB 10 speed cassette rather than road the shifting worked perfectly.

Pull ratio and derailleur geometry completely different. “Works” but not how I’d want my bike to ride

jonk – On a weird note using an MTB 10 speed cassette rather than road the shifting worked perfectly.

Interesting. I’m using a deore 9 spd mech to allow me to use a 11-34 10 spd cassette with my Ultegra 10 spd shifter.

If I could use an 11 spd Ultegra mech it would just give me a nice warm feeling.

Tell me more

Funnily enough, I’ve just logged in to ask a similar question.

I want to put an 11-32 cassette on my road bike. 10 speed ultegra.

I know I’m going to have to go for an mtb cassette but is there one more suited than the other? Is there any benefit of going for, say, SLX over Deore?

Also will I have to go for a specific chain or will any 10 speed do?

Any advice appreciated, thanks in advance.

I used an Ultegra chain and a Deore mech because it has a built in adjust (though you can use in line adjusters). MTB mech must be 9 spd, but you know that.

Good cables help.

Campag have wider spacing in the middle cogs, Shimano may do this for their road stuff?

Carefully set up (adjust the end stops for the 1st & 10th, and cable tension for 2nd & 9th) it works perfectly – better than many road only group sets at the end of the TdY sportive judging by the noise.

Thanks for the advice gents.

I’m going to try a Deore cassette with the ultegra mech first to see how it works. I need a new cassette for my pub bike so if it’s rough I’ll just swap it onto there. If it doesn’t work then will look at changing the mech but would like to avoid that if possible

In the past I’ve used a deore lx 9 speed mech, 9 speed tiagra shifters and a 34t 9 speed casette – worked perfectly.

I’m curious I know more about the 11 speed 6800 working well with an MTB cassette; do the 10 speed MTB cassettes have different spacing to a road 10 speed?

For now I’ve gone back to to a 6700 mech and “borrowed” the jockey wheels – shifting perfectly but an 11 to 34 would be awesome for the step hills.

10sp MTB cassettes are wider than 10sp road cassettes. If you fit the MTB cassette, you omit the spacer.

I’ve been useing a sram 11-32 cassette with ultegra 6700 for a while – didn’t have to take the spacer out & had absolutely no issues.