400ex wont run right

[Nick110]

my 400ex will run good for about 5 mins. then it will gradually lose power then start to bog at higher rpm's. if anyone can help please tell me. if u need more info please tell me. thanks

[2004exrider]

sounds like its overheating.

[Nick110]

what can i do to fix it. like run different oil or sumthin. plz help me i cant take not riding

[2004exrider]

check the jetting first. make sure you dont have any airleaks in intake or exhaust header. are valves adjusted right. hows the plug look (is it the right heat range plug?)

[Nick110]

ok i will check all of that stuff tomorrow if u can or anyone can think of anything else please tell me thanks