The G26 is a super easy engine to break in. I just use an ashless oil like Lawnboy, Ryobi, etc. mixed at 32:1 with regular unleaded and run a gallon or two of this through it. After a couple of tanks of ground running, the engine should run good enough to fly and you can do the rest of your break in in the air. Once the engine idles low, has a nice transition, and everything is generally stabilized, then you can either continue with this oil, or I prefer to switch to Amsoil System 2000 Racing Oil. You mix it at 50:1 and I use it with Premium Unleaded. This way, I can use the same gas for all of my engines (I mostly fly Brison). Don't mess with your needle valves until the engine has been pretty thoroughly broken in. I've had one where I never had to touch the needles even after break in! Either way, it's a lot easier than it is with glow engines.