I have an 04 450 all stock. A week at the most past since I last rode the thing and it usally starts on the second or thrid kick. Last night it took me forever to get it started to I could check the oil level, but it did start and I ran it for about 90 - 120 seconds or so. Today on the other hand, a perfect riding day, I got home from work really looking forward to a great afternoon of riding. I mounted the bike and after about 15 kicks I was out of breath. I tried putting it in 5th and rolling it as fast as I could just to hear it was sparking. It sounded like it wanted to start but I couldn't push it fast enough to do so that way. So I lay a good 25 or more kicks and it started and ran about 3 seconds and back firing to a stop. About 20 more kick only resulted in a very very pissed off yz450f owner! What could be the f..ing problem? I'm on my last nerve with this bike... if it keeps up I'll be purchasing a CRF450 or a .......dare I say.... a 660 raptor w / elctric start! Please calm me down.