It's not that hard to tune. Have you put a few drops down the carb and make sure you about a 1 mm opening, take off the airfilter to check. If you haven't touched the needles factory settings and the glowplug is good it should fire up after a few pulls or. You can check your glowplug take it out of the engine plug it into the ignitor and it should glow almost instantly if it doesn't then replace. If you have a pull start and it's hard to pull you've flooded the engine take the plug out and drain the cylinder. It could even be your glow plug ignitor. There are other reasons it won't start either but there are alot of people in here that know all the different problems there are. And you can't just tune an engine once, weather changes,altitude, the more it gets broke in, we are all here to help each other, so ask away.