I rejetted this morning , took out snorkel, runs great especially around and past 4k rpm, however before 4k rpm its kinda sluggish, however the bike starts and idles fine, am i not getting enough air? I ran it with the lid off and was kinda sluggish all the way around.

 

I did my wifes bike with the DJ 300 kit and followed the instructions for a KLX300R with the end cap on. I put a KLX300R exhaust and header on but am running with the end cap off and the air box lid off. It runs great throughout the whole range. What kind of exhaust and jet kit you get?
db

 

FMF Q4

 

The FMF jet kit i ordered did not have the pilot jet in it... could that cause the problems?

 

Nope


Why dont you post what you did instead of just figuring everyone will guess.

 

Stock alone the KLX is a bear under 4000rpm's. Mid range power is good but anything we can do to help the under 4000rpm range performance is a step in the right direction. The bike is an absolutezombie below 4000rpm's.

Mike

 

+1. What size of main jet did you install, and, looking down at the needle, which notch did you put the clip in?

Sounds like you are getting plenty of air...just not enough fuel.

 

128 main, i used a klx 300 fmf jet kit i put the clip on the 4th from the top like the kit said , i backed the fuel screw out 2.5 turns , which shoudl probaly be 2 turns, the airbox lid is on atm minus the snorkel.

 

As far as I know, the FMF and Dynojet kits are indentical. Maybe somebody with a Dynojet kit can chime-in. If that were the Keihin needle, it would be set too rich, but I'm not sure about the dynojet one.

Just to clarify, the 'top' of the needle is the end with the grooves, not the pointy end. That's just a broad sword statement because there have been people who thought the opposite was true.

Also make sure the needle is seated comletely into the slide. Some of the needles that come from Dynojet and FMF need to be smoothed out a abit before they seat completely into the slide and into the needle valve at the bottom of the carb bore.

 

I put the DJ kit in my wifes bike and put the clip in the 4th groove from the top as per instructions. I also put the 2 washers on top of the clip as I did not have a brass spacer as per the instructions. I drilled out the slide with the provided drill (#32) and set my Kientech screw at 2 1/2 turns but adjusted it closer to 2 turns after fine tuning it. I have the KLX300R exhaust and header with the end cap removed. Runs great. I rode it and I could feel a major difference from low to high and I weigh 240 lbs! My wife says it pulls the wheel off the ground when she shifts into second and gives it the gas (power wheely) but she only weighs 130 lbs....What elevation are you at?
db

edit: I forgot to mention I used the 128 main from the kit as per the instructions for a KLX300R with endcap on, figuring we were 50cc less so it would all work out, even though we have the end cap off. We also used the stock pilot jet. Oh yeah, UNI filter too