The K75 drive shaft is right at 32.85 cm. An R1100S drive shaft is right at 34.25 cm. They both have 16 input splines and 20 output splines(86 on). Assuming that the splines are the same size, the diameter of the shaft is the same or very close and the depth of the splines on the R1100s shaft are deep enough, couldn't you just machine 1.4 cm off the output side of the R1100S shaft and us it on a K75?
