This question will get you thousands of differing suggestions. Break in is supposed to get your engine into operating condition. Warm up depends on where you live, here in Texas at sea level warm up consists of starting the engine, removing the glow driver and clearing the engine of excess priming fluids. I adjust needles once after 2 to 3 hours of operation or if I happen to remove the needle valve completely from the engine. Most people mess with needle valves too much and get their engine out of whack. Here's a question for you, do you gentes and ladies get up every morning and tune your car's carburator before you go to work? I better qualify that all you non anal ladies and gentes. Have fun !!!!

Will