Phil, I haven't run it yet! Its been modified by my local model shop, Weston UK. All my other 4 strokes run on straight 20/80 fuel! I have used 10% nitro. This will be the first 4 stroke I've used in a C/L model!! should be fun, the crankcase and lugs are exactly the same size as the OS FP25! So if it doesn't work I have one I can stick in it. What size props work best on your Magnum 30 ? I had no problems running my other 4 strokes on Castor, I just used to flush them through with IPA, now and then, then oil after that.
Cheers Neville