I found some Mobil 1 75/90 so I'll have themput that in the trans. and the V-Twin in the other two and be done with it.

 

That's what I do. You'll be fine.

 

Why not? I used it there with zero problems. In fact, when I sent a quart of each, car & V-Twin, off to be analyzed there was so little difference between the two as far as additives, that I'd never pay the extra for the bike version. The additive that is supposedly responsible for the clutch slippage is the friction modifier molybdenum. The 15w-50 car oil had 79 ppm, and the 20w-50 bike oil had 91 ppm. Therefore, the bike oil oughtta cause slippage more easily than the car oil. Bottom line is there is essentially no difference between this particular additive, and the car oil won't cause slutch slippage. They're both too expensive to use in the primary, in my opinion.

And I'm moving this to the Oil Forum.

 

I get mine from G.I. Joes up here in Washington State. As for how much...READ YOUR OWNERS MANUAL.