I have a 2003 raptor that I just finished putting in a dynojet jet kit K&N hi flow air filter and a pro design airbox base plate, the elevation here is about 1600ft, theres a 142 main jet in the left carb and a 144 in the right, needles set on four groove from top, mixture screw on both carbs are three turns out. my proplem is when I'm in 1st gear and nail the gas there is a slight stumble before it gets up and going, then it runs strong all the way to red line, but I also notice the same stumble when in 2nd and 3rd and I hit the gas hard, 4th and 5th it really is not noticable. also going up a decent size hill in 1st it dosen't want to build the rpm's up, it just bogs, but in 2nd on the same hill with more gas/speed its fine
I think it may be a little rich on the mixture screws, but I would like some advise on how much to turn the screws on each carb. any suggestions would be great, its really killing my weelies.

 

To tune any carb you need to start by adjusting your float level, the tube method is the best way to do it. If you've allready done that I would try the 3rd groove on the needles. What air box mods do you have?

 

besides the K&N and pro design plate, I only cut the flaps out of the rubber boot type thing thats on the lid, and cut some plastic peices of the lid off to make room for the filter, I want to keep an airbox lid due to dusty conditions that I sometimes ride in.