BMW R 1100 RT Repair Manual page 260

Technical Data
Steering lock angle
Steering head tube dia.
Handlebar width with weights
32.6
R 850 R
° 2 x 37
mm (in) 22 (0.866)
mm (in) 780 (30.7087)
R 1100 R
2 x 37
22 (0.866)
780 (30.7087)