quote:

Irvine say that you should only use synthetic oils of you have 2% castor as well
chickens, old school wusses,

ever heard of a high performance motorbike running on castor?

Philly sorry to tell you but your a little wrong, the majority of the highly stressed Engines that run on methanol use castor based oil. Call it Castrol M ,Castrol R30,Castrol R40, Shell M. Call them motor cross,Scamblers, Racing bikes, 100cc karts, 250 cc karts, they still use castor based oil as these engines all run to very tight tolerances and don,t use rich mixtures.

and no I don't use Castor in my engines As I try not to run them lean to gain every bit of last power out of the engines.But if i did then I probaly would.