1987 Yamaha Warrior Problems

[honda200]

My 1987 Warrior, that i bought off of my bro because he decided to buy a 300 EX runs amazing for 20 min, then it just goes down the er, no top end in gears 4 - 6 but in 1-3 its alright, what would cause this? I have a Cobra Quiet/Utility pipe on it, and the guy I bought it from said not to rejet it if it runs good, Cobra said that too when I emailed them, should I rejet it? I just had it out tonight, bout 45 min then stopped at a friends house for an hour, and 45 min back home, it ran like a champ, kept up to my pop's 600 twin polaris sportsman, then it just went bad again, do I need to rejet? also, the black paint has like burnt off the pipe in a few spots, near the end and near the header and a bit in the middle

Thanks

P.S. ATC Crazy, I tried BlueTraxx forums, but i forgot my login and when i registered with my other account, i gave them the wrong email addy, dang

Curtis

[Honda300ex]

How does the plug look?? it should be a brownish color. It sounds like it might need rejeted.. Is it overheating?? Stuff dont run to good when it hot. Runing lean could make it over heat.

[honda200]

I took the plug out today, its is kinda whitish, about 2 or 3 shades lighter then tan, i also took it into the people where i bought my pipe, they are a yami dealer and all so i just took it in

Thanks for your help

Curtis

[Honda300ex]

Yea you where runing lean.. It should run right once they jet it correctly

[honda200]

Well, got it back from the shop yesterday, pulse coil in the stator was screwed, new stator was 600 bucks, they re jetted it, new spark plug boot, new carb gaskets and air filter and cage, total amount, over 1k

Ohh well, I aint sellin the bike anytime soon, i am going to keep it till I am at least 20 and slowly keep adding aftermarket parts

Curtis