[ChillyBear]

I'm not like an expert lol, but in general when I tune a two stroke by ear after say cleaning the carb etc, I would always adjust to peak rpm on an adjustable high jet if its a small carb, or just a richer jet if its a big carb on a not stock motor, and then richen until the rpm dropped a tad. Two strokes have a tendency for the exhaust temp to creep up under load. However, I think the main thing is flame speed as far as the rpm/power gain. Two strokes always run "extra" good right before they burn pistons. Or what moto-x/go kart guys call the "lean edge" something you find if you have the budget to rebuild motors every 3 hours, with custom micro polished clearances etc, it's so wasteful.

But I thought of my comment later, and realized that you probably have oil injection. I've never blown a jetski up. But I have death with jetski keinhin dual fuel pumps on my old go kart. It ran on methanol, so I got to experience a new fuel system clog every 3 days of sitting lol. But it had floatless carbs, holy crap what a nightmare to get the fuel pressure right.

Lean runaway will happen on two strokes at high rpm if they have vacuum leaks or carbon build up, or are being starved of fuel. OMG not fun. You can pull the plug wires and it will still diesel or whatever the hell it's doing, and will do some crazy stuff. Depending on the engine bore/stroke and the fuel, knock/ping can feel like a second/third power band, or it can just be a fast burning lean mix.

But vacuum leaks can cause that high idle, and will also (obviously) make it run lean. red rtv is your friend on a two stroke, my exhausts always have red +2000°f red rtv on them two. Its a nice feeling to KNOW your performance is from proper tuning and not from running lean. But cases, carbs, reed boxes, everything is COVERED in rtv.

I may also just trying to read between the lines, and took the "running good" and went off on a stoner tangent lol