Topic: cb750 which oilto use

[seanbarney41]

Not gonna tell ya what brand I prefer.  I will say what I have noticed, though.  Just about anything works good after a fresh oil change, but how long does it stay working good?  The better oils keep working, as evidenced by smooth shifts, easy neutrals, and good clutch action, for at least the full 1500 mile service interval

[jonda500]

well Castrol GTX must have had a different formula in Australia. I tried it in my 400-4 back in the eighties and the engine absolutely loved it, ran smoother than ever, but, the clutch started slipping the very next day and fast forward to the end, I had to put new friction discs in to fix it.
I actually have always adjusted my cam chain with the engine running - that way I can adjust it to be only just quiet, but without slowing down the idle speed at all!
John

[PeWe]

The 400-4 might have different needs than CB750? Must have thinner viscocity?

A friend has an Aprilia Falco 1000 year 2000 which seems to have very specific needs of oil.
More or less only the Motul semi 5100 10W-40 that works well without clutch issues according to the owner that had read Aprilia forums to sort all Aprilia issues that happened or will happen if not modify it.

I tried Motul 5100 20W-50 in my K6, gearbox felt better than with mineral 10W-40 but not as good as with Spectro HD 20W-50,  like the expensive Red Line 20W-50 esther synth. I tested Motul 7100 ( also full synth) too that smells very nice. Spectro had better gearbox feeling, smoother, not that mechanic.