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vaget22
05-07-2010, 10:12 AM
I have a friend with a 03 Predetor 500 that just picked up a White Bros Full system that he is going to install and I figure the jetting will need to be tweeked a bit. As far as I know everything is stock including the airbox. If everything is left as is do you guys think that bumping the main one or two sizes will be ok? He's not really looking for a bunch more power just wants a better sound. Any thoughts?
Predator Chaser
05-10-2010, 07:01 AM
I would bump the main up to 170-175
Pilot jet 47.5
needle jet arount the 3rd or 4th slot
air fuel screw about 3 turns out that should makeit run and sound great
dcc1089
05-10-2010, 11:24 AM
Actually, the Predators are jetted slightly rich from the factory. By adding only the exhaust, you may have to tweak the needle (one up) and a bit on the mixture screw. I would NOT go all the way to a 170-175 main jet or touch the pilot with a stock intake system. That is a HUGE jump from the factory 150 main jet.
Predator Chaser
05-10-2010, 12:28 PM
Im in Tucson have a 2006 Pred. 500 with a HFM slip on Big gun Headers K&N drop in running with the Jetting changes I mentioned above and I have great power all through the throttle from idle to WOT Im running just a little rich which i would rather do that than run lean.. but that is just my bike and it seems to work for me....
vaget22
05-10-2010, 12:32 PM
Thanks for the input guys. I'm open to all the info I can get for jetting his Predator. I've done a few other bikes but every model machine seems to have their own qwerks. Another question. Is there a plug that will need to be drilled out to get to the mixure screw? Not a huge deal as I've dealt with drilling them out before. Its just kind of nice knowing whats in store ahead of time. I figure I'll start with a 160 and look at the plug. Anybody know a thread where people post where they have their jetting setups?
dcc1089
05-10-2010, 01:14 PM
polarisriders dot com
AtvFan2010
05-11-2010, 09:02 AM
My outlaw ran perfectly fine with a 155 main jet. Your friend should be fine.. 170 is a huge jump way too much for just a pipe
craldad63
05-16-2010, 09:56 AM
155 main jet. per wilson racing and Johnny G sr. (rip)