Shimano GRX Compatibility Question?
Hello,
Does anyone know or can point to documentation as to whether or not you can use an RX-812 (long cage) rear derailleur on their normal 2X setup. I believe that the difference in cog sizes are 34 max on the 2X and 42 max on the 1X. The difference is only 8 teeth which I would hope would be made up with the long cage rear der.
I am working on speccing a new build with a 2X GRX drive train and would like the option to provide lower gearing if needed in the future without replacving the rear der. I know that this trick would work on older Shimano drive trains but don't know about this one.