I've only ever used Rock Oil except for 1/2 a bottle of Castrol R2 and I have heard questionable things about Motul regarding how thin it is, maybe there's that much of it in the mixture it's causing problems? My '28 ran on premix and the oil pump for the first tankfull when it was rebuilt and it was an absolute bitch to start.

I don't know much about Redline Racing but any manufacturer who claims to have seen a 5% improvement in power (I kid you not, 5%! Read the middle grey box here) by changing oil brands is probably best avoided at any cost.

Part of the problem with 2 stroke oil is even the cheapest nastiest £4 a litre duck oil passes the most stringent of industry standard tests. That and the fact we're always told not to mix brands and people tend to stick to what they know works.
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