Hi guys;
Question regarding the air intake mod you guys are doing with shop vac hoses and such.
I live at about 100'-200'ft above sea level, I was wondering if i would have to re-jet, with only this mod. I still have stock exhaust, also interested in drilling holes in the air breather cover(lid) wondering if this is necessary in conjunction with the bigger hose? Anyway my buddies and i went riding last week,and met up with a group of young fellas in the local sand and gravel pit... I went right over to a guy on a banshee and asked if we could have a little drag. I know what the banshee is and i had to settle my curiosity... we lined up, with one of my buddies at the finish. If i had to guess it was about 1000 ft or so on gravel. The banshee won by about 4-5 bike lengths. That thing can motor. I have to add that i had a fiberglass fairing with windshield as well as a Kimpex passenger trunk seat (wind resistance) but hey i still ran with one of the fastest production quads made and didn't get embarassed!!! I asked a guy on a piped and jetted warrior to race but he wouldn't . I now have a new respect for the big kaw, and was wondering how to close the gap. The banshee was stock by the way... and this guy could ride!! Watched him doing donuts and coming out of them in wheelies for a past time!!!
I realize that the 650 is not a sport quad, but it's still fun to pull up next to the sport quads and get some respect. Going riding tommorow in the mud with some buddies ,
one just got a suzuki quadrunner 500 with 27in. Mud-bugs and he wants to see if we can follow... probably not ( i saw his tires!!! )

Rob.

 

This is pure speculation but also an EWAG. The Prairie is jetted for about a 1000' altitude and it is jetted slightly lean for emissions. So if you open up the airbox I would say that yes you are definately going to have to re-jet to a richer setting for the altitude you are riding at.
You can try a plug read but my experience so far has been that plug reads are not that reliable.
Insulator color on a plug is more of an indication of plug heat range than anything else. I over oiled the airfilters for both of my quads and had them so restricted that the bowls on the carbs were running dry when trying to run at top speed. Should have been extremely rich right? Plug reads didn't really show them to be running as rich as they really were. A better indication seems to be the amount of carbon you can pick up by sticking your finger in the exhaust pipe. It was solid black after my filter fiasco. The insulator on the Suzuki was solid white but the side electrode was coated in carbon. The Kawasaki color was till showing sandy brown but it also had a lot of carbon on the metal portions of the plug. Both quads are supposed to run the CR7E. For some odd reason unbeknowest to me the Suzuki came with a CR8E. I figure this is why there is such a difference in plug color.