Hi Wardlaw,

The yamalube is 100% fine for the gearbox as the same will go for any plain normal 4T motor oil. Yes if you want you can use oil specially formulated for gearboxes like the Motul 5100 and fully synthetic oils but no difference in the long rung...The difference you will only feel for the 1st ride, after that its pretty much the same.

When it comes to 2T oil then only stick with the branded fully synthetic oils like Motul,putoline,castrol. It does not really matter as long as it is fully synthetic and when you have chosen the make for you then stick with that one since the viscosity between different brands differ so will affect your jetting.

Njoy your new toy !

Cheers
Mario