i screwed up i guess. put on a full exhuast and rode it cuz it seemed fine. then it bogged out and died. so then i tired jetting it even tho it wouldnt run right to begin with. so after a while i got frustrated and put all the stock parts on and it kept doing the same thing. it will idle fine for a while get up to tempature and die.

anyone know what i probably broke?

 

First of all... what is it?

 

07 z400

 

Did you open the air box up when you put on the exhaust?

 

nope kept it stock

 

Well I'm gonna say since the Z starts and idles fine, you didn't "break" anything (hopefully). You have a problem with the air/fuel ratio. When an aftermarket exhaust is put on, you need to let more air in, cause your letting more air out. Your post says you put everything back to stock, did it run OK before you started modding it?

 

yea it did. i took the exhaust off also. so the air fule ratio shouldnt be an issue if ist all stock again... shich is why i think something must have burned up or broken from running to lean.

 

I think you have a plugged up main jet. If your really worried about the engine just take a compression or leak down to make sure. If the compression is ok, it's more than likely a fuel air ratio issue.

 

i just put a aftermarket exhaust on my bike and a twin air filter and i havent jetted yet and no problems

 

my brother and his friend think it might be the valves. so we are gunna check them tomorrow.