I choo choo chose 29
I happened to be looking at a bike in Lbs while waiting. Was a gravel bike with GRX running a 42t. Noticed the hanger was longer and more horizontal than on my MTB’s (a bit more like a goat does). Wasn’t sure it it was just this bike or a thing that manufacturers are starting to do to better suit bigger cassettes.Current-series R7000 105 and R8000 Ultegra (and GRX derivatives) in long form will fit up to 42T without goats, and have enough play for a narrowish-range 2x ringset.