I want to use the shimano m5100 stuff with a more common bcd crankset then m5100 crankset. I believe the m5100 crankset is a 96mm by 4 and the grx is 110mm by 4 (which seems more common and easier to find different size chainring). If anyone has a better solution please let me know. Thank you in advance.
by InflationEastern8257
9 Comments
I’m guessing that shortage derailleur will be an issue.
The deore shifter sucks. It feels sluggish and i hated every shift with it. Do yourself a favor and get either the [SLX M7000](https://bike.shimano.com/en-EU/product/component/slx-m7000/SL-M7000-11-R.html) or [XT M8000](https://bike.shimano.com/en-EU/product/component/deorext-m8000/SL-M8000-R.html) shifter it’s like $10 more. Well worth it for crisp and fast shifts.
Crank is Crank so yes it fits.
Shimano technical site has a compatibility chart.
Get the SGS long cage
Only possible problems I forsee is with the BB, and being a1x setup I expect you’re going to buy narrow wide chainrings?
My bike came with this exact group set, except my derailleur was the long cage (rd m-5100 SGS) variant. I’m not 100% sure if you absolutely need the long cage, but I do assume so.
You can use any 11 speed crank so that is not the limiting factor. Buy a decent BB tho.
Don’t forget, the GRX cranks use the road spindle and thus are **not** compatible with a 73mm shell.
So if your frame has a 73mm threaded shell then those cranks won’t work.
To all the people commenting on the “short cage” derailleur:
I suspect there’s a mistake in the text description. As far as I know, there is no “short cage” variant of the M5100 derailleur. There is only the RD-M5100-SGS, which has enough capacity for the 11-51T cassette.
There is a smaller capacity derailleur in the same series, but it has a different model number (M5120-SGS).
Source: [https://bike.shimano.com/en-US/product/component/deore-m5100.html](https://bike.shimano.com/en-US/product/component/deore-m5100.html)