The best oil for the 315 in our opinion.
Despite the official line saying that is good for up to 40:1, we have used this for donkeys years at 80:1 in the 315. But we could not possibly tell you to do that, now could we........
The Go karting lads also use it, and they are revving their engines to the moon!
(Cannot be shipped outside the UK)
 
Castrol A747 is a very high performance, low ash, part synthetic lubricant with castor oil, specially formulated for use in multi-cylinder, water-cooled 2 stroke engines fitted to race machines, where combustion chamber deposit control is essential. Contains special additives to prevent throttle slide sticking in wet weather conditions and may be used mixed at fuel ratios of up to 40:1.