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Good price at £230 compared to buying the stand alone arms @ £300-325,
The Double chainrings can be sold on to contribute to a single chainring
I’m a little confused on the difference between M9100 M9120
Difference q factors and chain line
For a boost frame to run 1x12 which is the best set to buy is it the one with 52mm chainline, I already have a chainring to fit crm95
Available at psychic-cyclist.com
Doh... chainreaction / wiggle
I’m a little confused on the difference between M9100 M9120
Don't buy the 9100, they have a narrow q factor and probably won't clear the chain stays.
Thanks @damascus So go for the m9120 with 51.8 chainline and Qfactor 168 ?
I have the XT on but upgrading that onto my hardtail,
The Xt m8100 is 52 chainline and qfactor 172
Gets a little confusing , the last range m8000 had boost in the name
Gets a little confusing , the last range m8000 had boost in the name
I've had xtr 9000 and xtr 9020 cranks.
The 9000s hit the chainstays. I don't think the 9020 are boost, just a wider q factor. You can run an offset chain ring. Though.
I think the boost Chainset still say boost on them.
Many of us run normal Chainsets on boost frames with no problem but you need to fit to check.
But if I was buying new, I'd be looking for a boost set
Edit, just found this
Shimano XTR FC-M9120-1 Boost Crankset:Both the M9100 and M9120 single ring cranks share the same 52mm chain line. This is possible with some chain and chain ring technology. With a double we were not able to keep the chain line the same due to boost and non-boost, so the M9100 has a 48.8mm and the M9120 has a 51.8 chain line.
You’ll also notice lack of chainring bolts on the new cranks. We’ve gone away from them and moved to a direct mount style chainring for both single and double. If you’d like to switch back and forth between single and double rings it’s possible using the same crank arms.
For a single ring set up your chainring options will include 30, 32, 34, 36, and 38t (SM-CRM95). The only gearing option on the double is 38-28t. For the double, the large ring is direct mount and the small ring uses chainring bolts that thread into the large ring.
https://bike.shimano.com/en-EU/product/component/xtr-m9100/FC-M9120-1.html
This seems a useful article, I’ve just read recommended SM-BB93, smaller than a regular shimano BB was planning to use an MT800 or saint bb threaded 68/73
The latest 12 speed M91__ series no longer name them boost, which the m9000 did