KDXRIDER.NET

Working on a 05 KDX and decided to try a JD Jetting kit I've had for a while. Installed the kit (with recommended jets) and started the bike to warm it up. I'm pretty sure I'm right, but wanted to ask. I can turn the air screw all the way IN to the point that it seats in the carb and the bike will still run (blowing lots of smoke). Just did a pressure and vacuum test a week or two ago and know the motor is sound. The installed PJ is way too rich, correct? Leaving for a ride first thing in the morning and want to make sure I'm right before switching PJs.

Set screw at the best idle. If less then 1 you need richer pilot if more than 2 you need a leaner pilot

Never got that far. Too late (neighborhood) and too cold. I'm assuming best idle will be greater than 2 out since the bike would still run with the air screw all the way in. Not sure if I need to go smaller on the pilot or one step leaner on the needle clip. Guess I'll have to see how it goes tomorrow. Thanks.

Jetting guide...there are no shortcuts

Jetting guide..."As already stated, start with the pilot circuit. Turn the airscrew all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the airscrew slowly in, and then out, until you find the point where the idle is fastest. Stop there. Do not open the screw any farther, or your throttle response will be flat and mushy, and the bike may even bog. This is only the starting point, we will still have to tune the airscrew for the best response.

Now is the time to determine if you have the correct pilot installed in your carb. The airscrew position determines this for you, making it very simple. If your airscrew is less than 1 turn from closed, you need a larger pilot jet. If it is more than 2.5 turns from closed, you need a smaller pilot jet."


I have tried this and every time the idle speed continues to increase as the air screw is backed out. It never reaches a point where it stops increasing. I reach the point that the air screw is about "removed" from the carb and the idle speed is still increasing.

Am I doing something wrong here or is that just a sign that I am way too rich on the pilot jet?

That is the way I understand it. I always tend to go leaner as a first choice, as most bikes come too rich. It will feel flat or bog if you put too small of a pilot jet in.

I would think you need a leaner pilot. Or you need to check float height and the seal in jet nozzle. My bike will barley run though if I get a couple turns one way or the other from the sweet spot.