[Systolic]

Pulling my hair out on this one. Got a drop bar frame set with a 73mm width BB and a 142 rear hub (luckily a super long chainstay.) Trying to get the widest range drive train I can with a suitably low granny gear (17-20 gear inches.)

Would love to use all GRX, but the crank isn't compatible with a 73mm BB. I can swap to a XT crank, but then my concern is the GRX FD has a 2.8mm smaller chainline than the crank (would the end up being close enough?) If I swap to a XT FD then my concern is that the GRX shifter won't properly shift/move the XT FD. Thoughts? Help?!

 

[dave_rh]

Hi,

I don't know much about bb compatability with cranks. However prior to GRX being introduced. Many gravel bikes came with 105 or Ultegra with a 48/32 crank from FSA or some similar brand.

I suggest looking at giant, trek and specialized websites for their gravel bikes from around 2018 or early 2019. All 3 keep their old bikes online and can be found via a google search.

See what cranks those bikes are running such as FSA etc. One of those may fit your frame.