05 400EX jetting/intake questions

[400EXride]

I have an 05 400EX and I recently added a sport series slipon pipe from hmf along with a K&N intake/filter.

-Do I need to change the jetting on the carb?

I am by no means an expert but the quad seems to be running good. It starts right up and runs/sounds great. It doesn't seem to be running hot and throttle response is good at all points. I hate to start messing with the jetting if it isn't going to make a significant difference. If anything it might make the quad run crappy.

I talked with a tech at a honda dealer today and he didn't seem to think I would need to change the jetting. He thought it would only be an issue if I went with a full exhaust system and not just a slipon. He did discourage using a K&N filter saying it could allow dirt in the intake.

So what to do? Toss the K&N, change jetting??? Opinions???

[400exMO]

when you ride see if it feels different from before you had the pipe on. Also pull the plug, it should be a lighter brown, like a dark arm. WHite is to lean and dark brown is to rich. I'm thinking it should be to lean now. K@Ns are fine, I'm running one and love it. It's a great all around filter for everywhere, especially with an outerwears.

[400EXride]

It seems to run much stronger than before. The pipe sounds good and throttle response is right there. When it was all stock it sometimes appeared to be a little sluggish like it was loading up with fuel at times. It was definitely harder to start cold before the upgrades.

I just don't want to tear the thing up by not doing something I should........

[NCexRider]

i installed a k&n filter with outerwear and big gun slip-on on my '05. since i am not running an airbox lid i installed a dynojet 165 main jet and needle on the 3rd position, i am mucho pleased.