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Shimano R785 Di2 compatibility
I was one of those early adopters who went for Shimano R785 Di2 electronic gears and disc brakes. The shifters and disc brakes still work beautifully, but I want to change derailleurs and chainset. My question is, how compatible is the new (Ultegra) Di2 kit with the old R785 shifters?
Can I use Ultegra Di2 derailleurs with the old levers? Or GRX for that matter?
Could I switch to an internal battery (R785 used an external battery)?
Any thoughts much appreciated.
J
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5 comments
Thanks for the replies. I've just realised that as I don't have internal cabling (first gen Kinesis Tripster ATR Ti) I can't use an internal battery anyway. But I'll get the new Ultegra Di2 front and rear derailleurs, it sounds like they should be fine.
Could you drill a hole in an unobrusive area, and use a rubber grommet?
Thirded on the compatability with an internal battery; im using the latest bluetooth battery with some old R785 levers with no problems.
Im also using an xt rear mech; and given that the GRX kit is using tech copiedfrom ultegra and xt I cant see it being any issue. All Di2 (except 1st gen DADi2) is compatible; you do have to have matching mechs though to my knowledge (ie. no mixing groupsets when attached to the chainline) though im not sure if GRX and ultegra might play nicely given their common ancestry.
I've got R785 shifters on my CX bike with the newer internal battery. All fine with the new rear mech (1X setup of the CX bike) but not sure with GRX.
I've got the R785 shifters on my bike, but they came with the newer internal battery, so you shoulld be fine with swapping to an internal battery. The "brains" of the Di2 system are with the battery, so AFAIK changing to the internal one is effectively updating your Di2 system which means you can add bluetooth support etc.
I haven't tried changing the derailleurs for newer ones but I don't see why they wouldn't work. No idea about GRX compatibility.