Jetting for 366

[Superthrash1]

Hello folks, racking my brain here trying to figure this out. I have a Raptor 350 that I recently upgraded to a 366. I’m having trouble with the jets. No matter what jets I put in it stumbles and dies when I give it throttle. I contacted the manufacturer and they said start with a 147.5. Went all the way up to 160 with the same issue. I’m new to rejetting, thanks for any guidance

 

[ag2560]

Did you change the pilot jet also the stock one is a 22.5. I would put a 25 in it also depending on the year you may have to drill out the plug over the mixture screw to fine tune it. They come jetted lean from the factory.

 

[Superthrash1]

Just ordered a set of pilot jets. I have a jet kit that came with my wife’s Raptor 350 that has a variety it mains, but no pilots.

 

[beastlywarrior228]

Is it stumbling at full throttle with a gradual throttle increase?

 

[Superthrash1]

Been fighting with it all day. Again. It will idle fine with the 22.5 pilot jet, but no matter what main I put in, it stumbles and bogs badly. I can rev just a bit if I’m super easy on it. I went from 145-160 with no change. I tried a 25 pilot and it will rev good, but won’t idle at all.

 

[beastlywarrior228]

Been fighting with it all day. Again. It will idle fine with the 22.5 pilot jet, but no matter what main I put in, it stumbles and bogs badly. I can rev just a bit if I’m super easy on it. I went from 145-160 with no change. I tried a 25 pilot and it will rev good, but won’t idle at all.

You have another issue going on then. Could be the parking brake rev limiter.

 

[Superthrash1]

Got it figured out. Seems like the starter/air jet was the issue. Not sure if it was clogged, I just swapped it with another one and it’s all good

 

[beastlywarrior228]

Got it figured out. Seems like the starter/air jet was the issue. Not sure if it was clogged, I just swapped it with another one and it’s all good

Perfect! Seems to be running fine then?

 

[Superthrash1]

Yep. Thanks for the advice