the oil you run makes a big difference. when i ran regular oil it would do that. after i switched to mobil 1 15-50, it went away and the bike ran better. they have discontinued this oil now so i would find an alternative. i am going to try maxima ultra in my 450r. you shouldn't have a problem with maxima, amsoil, klotz, etc...
2005 450r
*sold* 2001 400ex
"If you think you can, you can. If you think you can't, your right."
"A leader will take you where you want to go. A great leader will not necessarily take you where you want to go but where you ought to be."
"If you want to do something, you will find a way; if you don't, you'll find and excuse!"
"Its not aptitude but attitude that determines your altitude."