OUCH! 16 bucks for 1 litre! I pay about 12bucks for 5!
The Mojo Motovert race teams run home brand Safeway oil, 20w50.
I know for a fact it is actually Shell 20w50 (you know the yellow one that's twice the price?). Good oil. I use it in everything.
The Lifan does seem to use a bit of oil. Mine is using a bit, but at 3 bucks a litre, it's not an issue.
some road race team though seem to think something like Castrol helps with engine wear, but this is different to dirt/ motoX where you're on and off the throttle a lot. In Motard/road racing we're doing upto 13,000rpm and 100kph full throttle for up to 10-12seconds.