Originally Posted by
Eric F
Something ain’t right…
Ultegra 6800 levers
XT 11-42 cassette
GRX 812 rear derailleur
I cannot get this combination to index properly. Not even close.
The SRAM 11-36 cassette that came off did not have a spacer. Neither did the original 11-32 Ultegra cassette. Both worked great with Ultegra levers and Ultegra RD. XT cassette needed a spacer behind the cassette to tighten on the freehub.
What’s going wrong? What are my options?
11s road need ~36mm freehub. The old MTB 11s cassettes have the same thickness as a 9-10s cassette so it needs the spacer. Is your setup working with a 11-32 cassette? if so, that will clear the shifter/derailleur compatibility.
With the big cassette, when does it not index? is it all of them or the biggest?
Have you checked the derailleur hanger? is it straight?
Can you post pictures?