I recently bought a DG Xccelertor stage 3 W/Spark Arrester exhaust system for my 2005 sportsman 500 HO. I was told by the seller by the exhaust was going to require me to re-jet the main jet one size bigger. The stock main jet is #155. What size should I go to? How hard Is it to Change the main jet? Would I have to take the whole carb off? Thanks

 

just go to a dealer and ask for the next size bigger then 155 which is 157 1/2# and no you should be able to pull the bowl off and go up thru the bottom i think.

 

You only need to re-jet if your engine determines so. You probably can do a WOT and plug chop and it will indicate what you need to do. The driver doesn't determine what size jet is needed the engine determines what size is needed by the way that it is burning, it will either be lean, correct mix, or rich.

A couple quick things that you can do is:
While running WOT rapidly decrease the throttle to 7/8 open if the engine runs better then you are jetted rich.
While running WOT and you choke it a little and the engine runs better then you are jetted a little to lean.

A correctly done WOT and plug chop is the correct way to really and more accurately determine what your engine needs.