I pulled the plug on my raptor today and noticed it was awful black. The bike is completly stock execpt for a K&N airfilter. I was just wondering what size jets would you step up to, since its all stock. Thanks for you help.

 

If the plug is black, you want to step down in jetting, not up. Black is rich, white is lean, and light tan is just right.

Here's a great link on jetting:
http://www.atvnews.com/output.cfm?id=33463

Hope this helps.
Mark

 

IF YOU BELEIVE YOUR RUNNING RICH TRY GOING DOWN ONE SIZE ON THE SMALL CARB. YOUR RAPTOR COMES WITH A 140/145 JETS. SWITCH THE 140 OUT FOR A 135. IF THIS ISN'T LEAN ENOUGH THEN GOTO THE NEXT SIZE DOWN ON YOUR OTHER CARB. ANOTHER SUGGESTION CHANGE OUT THE STOCK FILTER TO AN AFTERMARKET FILTER THIS WILL HELP YOUR CARBS. BREATHER EASIER. YOU COULD ALSO HAVE BLACKENED THE PLUG FROM USING THE CHOKE ALOT WHEN STARTING. TRY A NEW PLUG BEFORE ANYTHING. IT MAY BE ALL YOU NEED. THEY ALSO HAVE A HOTTER PLUG FOR THAT BIKE. JUST ASK YOUR DEALER.