Any specific reason why you’re using Yamalube at all?
There are lots of good 2 stroke oils out there that don’t cost 40 a gallon and are readily available. They all need to meet/exceed the same independent TC-W3 standard to be so certified and that standard includes actual testing.
A while back I signed on to a good saltwater fishing forum just to tap into the wealth of knowledge those guys had about 2-stroke outboards and especially big big bore ones.
Since many of these saltwater guys are running thousands of gallons of fuel and many gallons oil through their engines each year, IMO they are in a good position to offer advice what works over the long haul and with heavy use.
Interestingly enough, when I posed the question of what was the best VALUE in 2 stroke oil, the consensus answer was a lot more clear-cut than I expected:
Pennzoil Preimum Plus – Very low smoke, good protection, great price, available almost everywhere (Walmart, Menards, etc.) I started running Pennzoil and compared to to the Merc and OMC oil that I used to use, the smoke reduction was very noticeable.
The guys that insisted on running synthetic were behind Penzoil XLF or Amsoil. Again, the Pennzoil was delivering excellent value even in full synth.
BTW, interestingly enough, there is no technical definition of “full synthetic”. It’s up to the maker to determine that.
Interesting blog post on 2 stroke oils: http://www.thehulltruth.com/boating-forum/119273-2-stroke-oil-certification-article.html
Grouse