Originally Posted by
jonathanf2
Also I'm curious if swapping out the pulley wheels for smaller sized ones might make a difference in helping increase cassette capacity? For example the GRX 400 RD can accommodate 11-36t (w/ 11t lower wheel) in-spec and the GRX 810 RD only 11-34t (w/ 13t lower wheel). Though the GRX 10 speed is limited to 46:30t with 10 speed cranksets, while the GRX 11 speed can use either 46:30t or 48:31t.
I'm sure someone on here with better understanding of bike drivetrains can chime in!
I believe that a larger lower jockey wheel will increase the chain wrap while using a shorter length derailleur arm. Look at a big jockey wheel RD like some of the Acera group RDs. That is a reason for a 3 jockey wheel RD like a LePree.
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