Miggsb, Hi and welcome to the forum. I'm new to this too. As others will no doubt weigh in, the three things you need are fuel, compression and spark. From what you wrote, the only thing that is reasonably certain is good compression, so we'll assume that for now. Next, as for fuel. Did you winterize your gas with a product such as Stabil? If not, the fuel may simply be stale. Also, along these lines, the carb may be clogged up with varnish and need to be cleaned out. Next, check for spark with a "known good" plug. One easy way is to install it in the HT cable and ground it against the engine (the cooling fins will do). Turn on ignition and press the starter button while holding the plug against the engine. You're looking for a blue spark. If it's red or yellow , further electrical troubleshooting ( which is beyond my experience at the moment,alas) will be needed. But I'm sure that there are others here who will gladly take up the ball at this point. Anyway, don't panic. If as you say, the bike was running flawlessly last fall, It's probably something pretty simple. By the way, while you're at it, get yourself the "BULLET SERVICE MANUAL" by Mr. Pete Snydal. Our host sells it. It will give you a pretty good basic understanding of your machine. Chuck.