- R75/6 09/1973 > 08/1975 **TWIN DISC ONLY**
- R90/6 09/1973 > 08/1975 **TWIN DISC ONLY**
- R90S 09/1973 > 09/1975
D=16mm (Actual cylinder bore size 15.87mm)
Pattern kits are supplied with seals fitted. In comparison, the genuine BMW (ATE) kits are only supplied with the seals loose & require fitting. Incorrect fitment can lead to damaged seals.
This can lead to disaster as it is not possible to purchase ONLY replacement seals if you damage the ones in the original BMW ATE kit.