Teapot One is lukewarm on the 2021 R1250RS

[Grumpy Goat]

I thought a 19" front made a bike less turnable. The only benefit of a larger wheel is to ride over the bumps better...?

To my knowledge both statements are true.

All things being equal, a larger diameter wheel will have a higher mass and also a highter rotational moment of intertia and hence a higher resistance to turn, i.e. it would be less "flickable". With muscle memory, this increase (alone) from a 17" to a 19" wheel would be small, and could be overcompensated by the wider / more conventional bars of the GS compared with the RS, hence the possibility for greater preceived flickability. Of course front end geometry has a big part to play also, and the two bikes are quite different in this regard. (Rake/Trail (inches): GS: 24.1/3.8 vs RS: 26.7/4.4; depends on the source) The smaller these numbers the more "flickable" and the larger the better directional stability.

All has to do with balancing the variables to suite the mission profile.