I recently rejetted and I think I have 146/148 in my Raptor. I will double check and get back to you but anyway. When I am riding it, in first and second gear like when i push the throttle in a little it coughs a little and then as i am pushing in more all of a sudden it will pick up. Then in 3rd gear it tends to back fire when I rev it all the way up and then shift to 4th. I dosn't really backfire it just makes that sound like a harley does after they shift kinda. You know how they rev it all the way up and then pull the clutch in and and shift and it makes the grunt sound. Mine does that in 3rd gear shifting to 4th. I could be because of the exhaust mods that I did too. The baffle all the way down in I punched out and then I took the screen off the baffle at the end. I also shaved out the welds in my headers to give it more flow. I am running with no lid on my airbox. When I put the snorkel back on it dosn't do any of this but the hp is gone on the low end and the top end sucks too.

 

Cool, I'd say your engine is begging for some backpressure. Lose the exhaust and buy one made for what you are trying to do. You'll save a lot of engine life in the long run.

~HoundDog

 

I dont think its a back pressure issue because when I put the snorkel back on, it dosn't do it.

 

The problem is in the sizing of your main jets and position of the needles...
start by installing bigger main jets(it works with the snorkel on because it isn't allowing as much air into the mixture)
come back for fine tuning and needle adjustment

 

Yep 148/150 and start out with the clips on the 3rd groove. And check your float level.