Hi, I have a 2003 WR450F that's been standing in my garage for almost 4 years. I'm not able to start it. When I step on the kickstart (e-start broken) many times it won't start and a loud bang like a shotgun is the only thing that happens. I have filled up with new gasoline, new sparkplug and I'we cleaned the carb. I even tried to tow it after a car (because the kickstart broke off my bike), but it just sounds like I'm having a war on my street I've taken of the top of the engine, and it looks like the valves not stuck. Not being the best dirtbike mechanic, what to do? Can a broken woodruff key be the fault? The sparkplug is wet, and sparks. But is the timing wrong? Please help I'm from Norway, sorry for bad english.