Originally Posted By: "quarterliter"
I was speaking more specifically about auto oil. I wonder how badly it will shear in a wet sump.
I'll agree with kr_bitog here, it's the transmission in the "shared sump" paradigm that's hard on the oil's viscosity.
Originally Posted By: "kr_bitog"
I think typical auto oil will have less add pack to resists the wear coming from the mechanical gear mesh, and it is quite typical the same oil used for 5k on car will need to be changed every 1.5K in share sump motorbike.
I think Mobil 1 auto Racing oil is anything but typical car oil, it's a different balance of additives from the standard street car Mobil 1, and AFE, HM, and EP.
With that being said, I thought that from Mobil 1's development work with McLaren Ilmor and Mercedes F-1 they got the best VII's in the add pack and other race-orientated features... so if you could get around the the very high concentration of moly friction modifiers (FM) without putting new meaning to the term "slipper" clutch on your bike, did't mind the 2500 - 3000 ppm zddp attacking your cats like a mad dog, had no objection to high levels of silicates for anti-foaming at high temperature/ redline operation, and weren't worried about the rather paultry dosage of detergents and TBN fortification it might go a long ways because the base oils likely have a very high and stabile viscosity index that requires a fairly low level of those top shelf VII's. Same with the fairly high HTHSV & very low NOACK.
But the common practice for racers using M1 auto Racing oil is to run one event and replace when doing the subsequent teardown. M1 auto Racing is best used with high valve spring rates, bearing loads, fuel dilution, high temperature, and no catalytic converters.
Similarly, if you had to describe Motul's 300V's exposure in the racing world, you might notice it's not only popular with the Moto GP and World Superbike teams, but alot of endurance sports cars racers seem to prefer some flavors of the auto version. 24 Hours of Le Mans, Daytona, Nurburgring etc. With decent detergent level and starting TBN, Motul 300V is also marketed to high zoot supercars and (sometimes modded-) performance street cars.
M1 auto Racing recommends itself strictly for auto racing. I'd be interested to see who's running it successfully in a wet clutch shared sump bike and have good UOA's to back it up.