Yup, 2.5 turns will be very rich. When tuned, mine runs somewhere between 1 and 1.5 turns out.

Throttling up a very rich engine must be done very slowly, or it'll flood out. Keeping the glow ignitor attached until you've leaned the needle until the engine sound suddenly jumps from that rough fuel spitting 4 stroke sound to a smooth, powerful, furious 2 stroke scream helps.

Once the engine is started, move behind the engine. Slowly advance the throttle to full.

The engine is running rough. Notice the raw fuel spitting from the exhaust. Slowly turn the needle valve clockwise (close, lean) a couple clicks at a time. The engine will accelerate with each tweak. Then suddenly the engine will smooth drastically. Just into this smooth, powerful running area is about where we start breaking in the engine. Never break in a non-ringed engine in the rough running 4 stroke tune.

As the needle is closed more and more, the engine will continue to accelerate. Then you'll click leaner still, and there'll be no change. Go further and the engine will quit. Rich the needle half a turn and restart. Once you reach that no-change area, we rich the mixture just enough to hear a slight drop in engine speed, 3-400 rpm if you have a tach. That's flying tune.

Be careful, have fun, and good luck!

J