31-07-12, 09:05 PM
When Yamaha came out with the 12mm nut they also recommended 90Nm torque instead of the previous 70Nm with the 9mm nut. They must have thoroughly tested this, but like you I was concerned at stripping the thread so stuck with the 70Nm. I also used nut locking compound and the locking washer and have not had any problems. Using three sides of the lockwasher sounds a good idea though.