ORIGINAL: portanav
Thanks to all for your suggestions and comments; concerning the fuel it's ''Cool Fuel'' 15% 4 stroke, not sure how much castor is in the mix, I am running her at 7500 rpm using a 16x8 Master Airscrew at peak I am getting 8200, there are no loose muffler connections although I like the idea of the ''Teflon'' tape but concerned about the temp and its effect on the tape. Hope this helps with any conclusions.
Thanks again.
I have a couple of the 1.20 and don't recall any black oil, gray for the first few tanks but it clears up pretty fast and then is clear as can be. Being as they have a header and the muffler connects to that if you have something loose I would think you would notice it? Tighten the header and muffler with the engine at running temp. There isn't any need for the tape but heat has no effect on it if you decide to use it. Mine all had the one piece muffler and there is no baffle to come loose to give the nasty dark gunk. They may have changed that sense I bought my last one?