High-G FJR Junkie!
Join Date: Dec 2013
Location: Little Rock, Arkansas
I think there is an allowable range of viscosities that can be considered a 20, a 30, etc., and it's possible that the upper end of one range might be very close to the lower end of the other.
I think it's evident that maybe it's not as critical as many of us try to make it -- including me. Otherwise, how would so many people second guess the manufacturers and use thicker than suggested oils for decades with no problems?
At least Yamaha give us a range.
Just keepin' up with traffic, Officer.