i have a 2000 trail blazer i just put a 180 main in it.to cut down on the spitting & loss of power.i was just wondering how i could fix it.is it the spark plug or does something need adjusted.buy the way should i buy a 500 scrambler or a 400or a 400ex?

 

What other mods have you done? A .180 is a pretty big jet if it's stock. I've got a .170 in mine with a k&n, airbox mods, pipe and clutch.

 

You may be too rich, sputtering and loss of power can mean too rich, always check your plug coloring, white is too lean, black is too rich a light brown is good.

 

no it is stock what size main jet should it have.if its running rich how can i fix that.& if its running lean how do i fix that...........thanks

 

I'd think a .150 is probably as high as youd want to go with a stock 250. I believe you should normally jet down in the summer, (can't remember for sure, i just adjust my air screw and needle) and you've probably got a .130 or .140 in it stock. At any rate, watch your plug and use the guidelines above. If your not sure you might want to have your dealer take care of it, if you get it too lean you'll blow the motor.