I think one of the big contributors to these failures has been the quality of the lubricant. Many people have said the recommended BMW lubricant is not optimum for the task and nowadays many are using Hondamoly or similar.
Regards,
K-BIKE

A bit of information. Today I took a ride. Ambient temperature was around 35c and the ride was a mix of expressway and twisty stuff around the coast road. Got home in about 45min.

I have a point-and-measure IR thermometer, so I took some temperatures at different points:
a. sump was around 87C
b. clutch housing 60C
c. gearbox 60C
d. front and back of the shaft drive hosing 55C

I think that the temperature gets a bit higher inside.

Now the upper temp working limit for normal high temp grease is around 120C and it may get to that at the point of metal to metal contact where splines rub together. This is probably the reason we use Moly assembly/spline lube compounds.

Ned:

I have used Digital temp units for years..
They tell a lot about hot spots and they are a reasonable purchase for the shop.

Good Idea to share.


Sprocket"