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Shimano GRX812 rear derailleur - alternatives
New Gravel bike one week old - 11-42 cassette, wrecked the rear derailleur. Being told 27th August for part. Does anyone know of any other options to fit that will work with that range? This is depressing [:(]
If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.
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5 comments
105 R7000 GS is about as close as you'll get until you can get the right one. Might be able to swap some bits over depending on what you've broken but you might not be able to make it shift to the 42 either
The 40T should be OK with the R7000 GS (or the R8000 or even 6800 GS, the Shadow-based mech are apparently better though) but 42T would be a stretch without a hanger extender (look on eBay for RoadLink-alikes for a few quid).. or indeed most Shimano 11-speed or newer 10-speed road stuff in medium/long cage. Won't have the clutch, hence suggesting the GRX 400, but that may not be a massive issue to the OP.
Left field might be an S-Ride RD-M520C rear mech if there's one you can get.
https://www.youtube.com/watch?v=PxjONoCjiK8&ab_channel=PathLessPedaled
This might work with a Wolftooth Roadlink or similar together with a longer b-screw. As might a Ultegra RX800 11sp mech - it has a clutch.
GRX 400 10sp mech is the better option though - same pull ratio as 11speed, and less of a teeth "stretch" as Shimano say 36t is the max rather than the usual 34.
You should be able to use a GRX 400 rear mech if you can get hold of one.
Good advice. Backed up here : https://bicycles.stackexchange.com/questions/66631/is-the-cable-pull-of-...