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New chain/cassette soon for my Topstone and I was thinking about increasing gear range a little. I'm currently using 46/30 and 11-34T. I see there's now a Tiagra 11 speed 11-36T cassette so any feedback on that (or other options) would be grand.
I do have a new 11-40T XT cassette I could try but that feels just a step too far 😂
I reckon it'll work although I think that the 810 rear mech. is only really meant to take a 34T biggest cog & 46/30 11-34 probably puts everything at full capacity.
I can only speak from a GRX400 perspective and was running the default 46/30 11-36 setup (again, the drivetrain's at full capacity).
When I wanted to widen the range I stuck a 28T inner ring on. Technically this put both the front & rear mechs. over capacity but both shift perfectly.
There was slop in the small/small combo. but I'd cut the chain according to Shimano's new guide of counting back 4 links. Cutting the chain by counting back 2 links (the older style) removed the slop & I can still shift big/big without breaking anything,
Similar but not really... I'm running 105 GS on my gravel bike 2x to that 11-40 XT cassette you reference - with a goat/road link. The 105 der has a similar capacity to the GRX (39 total capacity for 105, 40 for GRX both largest sprocket of 34t). I can get all combos (I use 48/32 sub compact up front) though the chain is a bit floppy in 32 to the smallest 3 sprockets. It doesn't skip in these but I avoid anyhoo.
I would just wop on the 11-40 and see.... In fact I'm planning a wider range on my bike, all arrives this week, my only concern is gear gaps...
46/30 and 11-40 works. @ahsat has had it running for years. I’m very envious when we going touring and the bikes are loaded 😝
I've got an old Ultegra RX mech running a Sunrace 11-36 cassette with 48/31 up front, no problemscat all 👍
A few years ago I ran a 105 11spd rear mech with 48-32 and 11-40, with no Wolf Tooth link. All worked fine but had to get chain length and B screw adjustment spot on. Consensus seems to be that Shimano rear mech capacity figures are pretty conservative, but don't blame me if you destroy your rear mech the 1st time you put it in big-big!
This says I’ll be fine
https://road.cc/content/feature/how-get-ultra-low-gearing-gravel-bike-adventures-246424
This says I’ll be fine
https://road.cc/content/feature/how-get-ultra-low-gearing-gravel-bike-adventures-246424
Yes it was that very article that led me to re-do my gravel bike as per a couple of posts up-thread.
I've run a 40t cassette on two different bikes with GRX no problems for yearss
