I know, I know, trial and error but this is wierd. while jetting my Predator my friend had me jet up his Raptor. It ran fine before but a little lean (greyish color on the plug) so we went up a little on each carb. Why they use different sizes on each one is beyond me but they do, factory is a 140 and a 145 we went to a 150 and 155. Now, it sputters and pops from 3/4 to wot. It seems like it is starving bad but you would think it would have been worse with the smaller jets. It has a slip on and 12- 1 inch holes in the air box with a replacement UNI filter. Also, my Pred is doing the same thing I went to 170 main and 50 pilot and a UNI clamp on filter directly at the carb. The only other thing I have doneto mine is a Polaris slip on. Any wisdom would be appreciated. By the way we are at about 1100 feet. Help???

 

The jetting sounds about right maybe you bumped the floats when doing it and the float level is off. Try checking the level with a piece of 1/8" clear tubing, it only take a couple of minutes.

 

They sputter and pop when they are too rich too, just look at your plug when in doubt.

 

that jetting sounds a bit rich for a uni filter. they don't flow like a k&n. You might want to try dropping a jet size and use the carb needles to fine tune it.

Oh, and the reason for the staggered jet sizes in the raptor carbs is that there are three intake valves. The right side feeds two while the left side feeds one. Ergo, the right side needs more fuel.


~HoundDog

 

FUC% re-jetting...take that stupid snorkle and cut the airbox lid in a fashion it allows max flow but is still held in place by the clips...it will run way better...holes won't cut it

 

iblamethedog-raptorjay has it right ,lose the lid and snorkle and re jet and you will see an improvement in performance.i did not want to remove my lid and snorkle at first because i run in sand only but once i did and jetted up it made a huge difference.the raptor with its dual carbs is very critical as far as proper jetting is concerned but it is worth the effort to get it right.

 

Yeah I think that is where we are headed with this one. Off with the lid and keep tweeking it til it is right.