Originally Posted by Caddy82rats
The ST use the same calipier so the 4 pots conversion would work
Nope, the BMW 4-piston caliper does not work on a G/S nor ST.... I can tell you that for sure.
Boxerworks sells a machined adapter to do this mod, but the caliper ends up almost below the wheel and looks to be in a bad place for off-road riding.