I currently have the prerequisite "on-trend" gravel bike running the latest Ultegra R8000 with 50/34 front and 11-32 rear cassette with medium cage rear mech.
I am taking part in Torino-Nice Rally this year with it's 20,000m of climbing and am trying to gear the bike as low as possible, so that i can spin as much as possible with loaded bike.
i have 10 speed XT M785 cranks with 38/24 double rings, i've been told that they should work OK with the 11 speed chain?
In addition, i have both a 36 and a 42 XT rear cassette.
I know that i'll need to fit MTB BB, and if i try and use the 42 cassette i'll need the Roadlink thingy to drop mech down.
I presume my real issue is trying to get the front mech to work and clearances?
Anyone tried similar?
(Before i get lots of MTFU and toughen princess replies, i have been training hard but i am still an old prop forward that lives in Norfolk)
You should only need to lower the front mech ( and maybe adjust it for the wider chainline of the MTB cranks?), plenty of people have run similar MTB cranks on cross bikes for years.
I presume my real issue is trying to get the front mech to work and clearances?
The front mech won't work right, or won't work at all, that's the main problem. If it's braze on not clamp on it might also not be able to go low enough. Sadly MTB front derailleurs have a different pull ratio so you can't use them either.
Clearances, not an issue. You're putting on smaller chainrings AND possibly BB spacers, the clearance will be better.
I would get an 11-42 with a Wolftooth, and a 46/30 crankset.
But if you have the crankset already just get a BB and slap them on and you'll see if it works or not. Not a big expense.
The front mech is clamp on. I wonder as normal Compact road cranks are 16t difference and the MTB are 14t difference that not that much in difference?
I did try 46 and 30t Absolute Black front oval chainrings but as they fitted the Ultegra cranks and were therefore using road BB, the small oval inner ring fouled the frame.
I'd say yes. The setup for my roadrat may help-
-10s 105 shifters
-10s 105 front mech
-10s deore rear mech plus wolftooth tanpan
-SLX triple cranks with 28-40 mounted on inner and middle
-11-36 10s cassette
All plays together pretty happily.
I'd guess the rear mech would limit your ability to run a very wide gear range, mainly down to cage length/capacity. I'd consider an 11s tanpan and a 11s MTB rear mech. That would probably give you enough to take up all the chain slack. I also have a 1x11 cross bike set up like this and it plays together very well.
Thanks Swanny. Here's hoping it works, if not then i'll seek an MTB rear mech instead