CAUTION: This is a ringed engine, so don't treat it like you would an ABC or ABN engine. It must be broken in very rich.

How warm is the engine when you're trying to restart it? I've found that many engines are difficult to start when they're still hot because the compression is slightly lower and the fuel evaporates too quickly. Let it cool down between runs. This will also improve your break-in.

Make sure the engine is primed. Some engines like to "start wet" as I like to put it. That means it needs a good healthy prime - but don't hydrolock it! This is where a chicken stick comes in handy.

You should not need to touch the needle valves to restart the engine. If you do, just slightly richen the high speed needle. You may be leaning it out just a bit too far once you have it running.

Brad