I just bought this 98 YZ400 about a month ago. It ran really good, and there were no problems. Now it has been in my shed for two straight weeks, with temperatures outside getting to 105 degrees (I live north of Dallas, TX). I pulled it out last night to start it up. It kicked over just fine, but every time I touched the throttle, it bogged down really bad. I could never get the throttle to rev the engine at all, it only killed the motor like it was flooding it out. I need some advice on what to do to investigate the problem. Did the extreme heat in my shed screw up something? It haas easily reached 120 degrees inside the shed. Or is there something else I need to look at? I need to fix this so I can get ready for fall riding.