I was about to order a pipe for my Warrior and didn't know if I should buy the K&N jet kit or order the jets I need from Yamaha. Do you think the K&N jet kit is any better than just replacing the main jet with one from Yamaha? I was told if you buy the K&N kit you can't replace only the main jet, that you have to install the hole kit, needle, clip, main jet, and adapter. What do you think?

 

I think the K&N jet kit helped a lot on my Mojave. Yes there is a new needle with a c-clip for adjusting it for your mods along with a new pilot jet I believe it was. Example, if you have a high flow filter,jet kit and exhaust you put the clip on a certain notch. If you just have the jet kit you put it on a different notch and so on. There was no adapter with my kit, but the Warrior could be different. The kit is supposedly dyno tested and they give you a card for a free dyno run, there is a list of the closest places you can take it to and get it tested. I haven't had mine tested, but I would like to this summer. One other note, I put the filter,jet kit and a Cobra exhaust all on at the same time and was very pleased with the results. I have since taken the Cobra pipe off and went back to stock and I think it feels stronger from bottom to mid rpm's. The only place it lost out on is the very top end where the stock pipe just wont let it breath enough to hit the rev limiter the way the Cobra did. Everywhere else though I think the stock pipe is better. I would recommend a tunable disc type exhaust even though they're more money.