My 2011 yz250f I bought new just a couple weeks ago from the showroom floor as s left over and it is acting up. I only ran it like 4 hours now on the brand new everything. I never hit the limiter. It now will not kick start and just bumps starts. I dud get it too kick with a little starting fluid. It's not smoking or making wierd noises and once it's running it runs great. I took apart the top end and did a compression test and all that. Everything looks good and the top ends great. Compression is pefect. I'm lost with what this could be. It's getting good gas and good air and spark. Fresh changed oil and clean filter. Has a hour meter from the first day the shop got it. It read .1 when u bought it now it reads 4.6 so I put 4 and a half hours on it. I bought the bike when I got my 14 yz450f cuz it was too good of a deal ($4100) and the 14 has 5.8 hours and had 0 when I got it and is good. I could take the 250 to the shop but then it'd take them 2 weeks to repair cuz there slow. Most people around here bring there bikes to my shop but when I get lost I come to you guys! So any ideas of what this could be?