Okay, now I suddenly AM nervous.
directly from Motul
http://www.motul.fr/uk/conseils/faq/reponses.html
Oil for bikes/ Oil for cars. What is the difference ?
Most of 4 stroke bike gearboxes use engine oil as a lube. To reduce wear and increase gearbox life, we include gear additives into bike 4 stroke engine oils. And the oil must not perturb clutch efficiency.
For bike oils, the JASO (Japanese manufacturer association) is very concerned by the clutch sliding problem so they issued some requirements and standards. Motul 5100 and 3000 oils for 4 stroke engine bikes are JASO MA approved. To complete that, Motul performed the JASO T904 tests on 300V's to be sure that 300V's work properly without any clutch problem. On the other hand, for cars, there is no gearbox or clutch problem therefore we can use for example friction modifier additives to reduce friction into the engine. This will provide power output improvement. For bikes we strongly recommend to use bike oils and for cars, we strongly recommend to use car oils.
What is the difference between 4T engine oils for cars and 4T oils for motorcycles?
The main difference between the two vehicles is that the majority of four-stroke motorcycle gearboxes are lubricated by the engine oil. In order to reduce pinion wear and increase the life of the gearbox, MOTUL incorporates 'Extreme Pressure' additives to motorcycle 4T oils.
However, the factory data sheet for what I put in reads:
"Race bikes fitted with high performance 4 stroke engines,
integrated gearbox or not, wet or dry clutch, race engines running over a wide range of temperatures and RPM. Other uses: street bikes, scooters, ATV, mopes fitted with catalytic converters."
The statement above still leads me to believe it's safe. It's designed to work in motors that do not use a common-sump for the tranny and engine, and the friction modifiers should assist in engine operation anyways. Bikes are very hard on oil so this should be MORE than adequate for my car.
Right?