Best oil to use in the Crankcase

[AnthonyB]

I just rebuilt the top end on my 81 250R and i was wanted to change the Crankcase oil, But I don't know what type of oil is called for, or what would be the best to use.

[Flyingw]

That answer is somewhat subjective. The factory manual calls for 10W-30 but that was based on 80s technology oil. Since then, huge advancements in oil technology have been made in oil manufacturing but those advancements have made the run of the mill 10W-30 oil less condusive to wet clutch applications. This is where the arguments is. I still run 10W-30 in my trikes with no problems but if you want to be safe, use Maxima MTL (Motorcycle Transmission Lube) 80W. This is made for wet clutch applications as is several other brands of oil. Whatever oil you decide to go with, be sure its made for wet clutch transmissions.

[AnthonyB]

Ok Thank You very much, ill go down to my bike shop and see what they have.