10 speed and 11 speed compatibility question

[pamountainbiker]

Hi all,

Looking to add an older 2007 Shimano XTR M970 rear derailleur to a road bike and pair it with Ultegra 6800 11 speed shifters. Is this even possible? Searched The Google and while it won't work with a Dynasys rear der, my old XTR unit is not Dynasys (pre Dynasys), so the info I've found is inconclusive. I'm building up a gravel bike and have a nearly NOS condition M970 rear der which would be nice to use if I can.

Thanks!

[ITTY]

You will most likely be disappointed by shifting performance, but the derailleur will move the chain...

[pamountainbiker]

Thanks, I think I figured it out. A 9 speed Shimano mountain derailleur will that is pre Dynasys will work with 11 speed Ultegra 6800. It should shift normally.

[kramnnim]

Hmm, does that mean that a 6800 RD would work with 10sp shifters/cassette?