Running a larger cassette with di2?

[XXtwindad]

My new gravel steed has a ton of clearance in back for wider tires, but it's wired for di2. I really don't want to be tackling some of the fire roads in my area with an 11-32. I recently spoke with a guy who ran the XTR M9050 derailleur in back and paired it with an 11-46. I'd probably go with an 11-40.

Does anyone have any experience with this set-up?

Thanks.

[Lovetoclimb]

You have a couple options. With a 2x setup I am using the Ultegra rx di2 rear derailleur, XT 11-40 cassette and the wolftooth roadlink for direct mount. Took some work by the mechanic, some phone calls to Shimano, but it works great.

Other option is a 1x system and then just use an XT or XTR rear derailleur. Lots of di2 1x gravel backs come this way now, the Ibis Hakka my friend rides included.

[XXtwindad]

Originally Posted by Lovetoclimb

You have a couple options. With a 2x setup I am using the Ultegra rx di2 rear derailleur, XT 11-40 cassette and the wolftooth roadlink for direct mount. Took some work by the mechanic, some phone calls to Shimano, but it works great.

Other option is a 1x system and then just use an XT or XTR rear derailleur. Lots of di2 1x gravel backs come this way now, the Ibis Hakka my friend rides included.

LTC -

Thanks Bud! Exactly the info I was looking for. Should come in handy for Mt. Mitchell, too...

J

[dem]

Yup, I have 11-40 on both a 6800 Di2+Wolftooth, and an R8000-GS (same geo as the Di2)

You can also go 1X as indicated with the XTR RD.. but you CANNOT mix a road FD and a MTB RD as a double, Shimano firmware will not allow it.

[Spdntrxi]

Dem is correct.. no mixing of derailleurs

1x not a real problem.

2x the XTR FD does not move the the left as far as a road FD.. so potentially this will be a sore spot. 68mm road BB vs 73mm MTB. Not impossible but need to consider.

[Look585]

The Ultegra 8050 GS (and RX805) will easily clear an 11-40 cassette with no modification on most frames. I am running a completely stock Di2 setup with 8050GS, 11-40 (XT) cassette, and 46-34 chainrings. You probably will not need the Wolftooth extender with the 8050GS (you probably would with a 6870GS).

In some setups the RX805 will have too much tension with the clutch engaged and the protection circuit will engage and prevent shifts (thinking there is something jammed in R.Mech). You can move the tension spring to the lower setting and usually get it to work. The standard 8050GS doesn’t seem to have this problem (as there is no clutch).

As an aside, it appears there is plenty of clearance to go up to an 11-42 cassette in my system, but I haven’t tried it yet.

[XXtwindad]

Originally Posted by Look585

The Ultegra 8050 GS (and RX805) will easily clear an 11-40 cassette with no modification on most frames. I am running a completely stock Di2 setup with 8050GS, 11-40 (XT) cassette, and 46-34 chainrings. You probably will not need the Wolftooth extender with the 8050GS (you probably would with a 6870GS).

In some setups the RX805 will have too much tension with the clutch engaged and the protection circuit will engage and prevent shifts (thinking there is something jammed in R.Mech). You can move the tension spring to the lower setting and usually get it to work. The standard 8050GS doesn’t seem to have this problem (as there is no clutch).

As an aside, it appears there is plenty of clearance to go up to an 11-42 cassette in my system, but I haven’t tried it yet.

Really appreciate this and the previous posts. Super helpful.