[Grasshopper67]

Just bought a Baja minibike and don't have the owner's manual, it is used of course. Anyway, it has a little 97cc engine in it. What weight oil should I use? It won't be operated at temps under 60F. Thanks.

 

[DTLMG]

The Chinese will say 15w40 as this is what they use in them over there. I have done extensive testing both there and here with SAE 30 and 10w30.
My recommendation is SAE 30.

 

[hankll]

:ditto: "Not a Master Technician", but run a lawnmower service company, and I recommend 30wt for any engine. Multi-viscosity seems to me to be too light weight. I have no technical proof of that, just my gut feeling on the sounds of a fresh oil change using multi-viscosity or straight weight oil. I go an even further step in adding STP to the oil for just a little more protection.