Hi Pallla,
A good point! I live in Thailand and I can’t buy SAE 30 for love or money. Local scooter shops advise SAE 40 which is 4 stroke oil ,as most of the smaller bikes are .
Personally, I run Castrol LT 40, and change it every 1500 K’s or so.
It seems okay.
Cheers Grimesy.
the gearbox oil use this kind for viscosity reason.
It is not forbidden using high tech oil if you want to spend more money but people that I know and myself when using high tech oil of same viscosity didn’t gain at a long run either more protection or reliability. But if you like the idea…