Ok so i've removed the smog system, got the kdx snorkel and 5 air vents on the airbox lid, installed the crankcase breather kit from fourstrokeworks, UNI air filter and now I'm just waiting on some parts ie: N1TC needle, #40 pilot jet, kouba screwand either an FMF, muzzy or Big gun exhaust system. So heres my question:

I'm riding at over 3000ft, usually over 3500 actually and want to make sure i got my jetting straight. using the #40 pilot jet, exhaust (hoepfully the FMF Q4 and powerbomb) and i'm thinking 125 main jet? Also going to go with 2.5 turns out with the screw and 2nd slot on the needle.Does this setup sound right? I cant really seem to find a solid solution with the main jet size.

Thanks

 

that sounds like a good place to start...... then you can go fromt there....

 

Thats a funny Avatar. I was just wondering, you went one way and your helmet and gloves went the other. How does that happen?

 

In reality, only trial and error will get you where you want to be with the jetting. I have the setup noted in my signature with the exception of the pilot which I set back to the stock 35 last night. I'm about 2800 ft and with the 38 pilot I was getting pretty severe carbon fouling, misfire at constantthrottle positionwithin the pilot cuircutrange (0 - 1/8), the bike would cold start with no choke, there was a lingering stench of fuel, and a slight bog/hesitation when nailing the throttle from down low. I rode about 12 miles this morning and with the stock pilot, all symptoms are gone (except I still need to check the plug to see if it's fouling).

Thepilot size is most affected by the airbox/smog system mods. Meaning that since you did them, you'll probably want to up the stock pilot but a 40 might be a little too big. Of course, the only way to know is to try it out. Also, as far as the kouba screw goes, I would not recommend it. I think it's about 50/50 as far as whether people like it. I don't because while the idea of being able to adjust it on the bike is great, mine was so hard to turn that I could not do it on the bike. That's just my experience. Others might sing its praise.

I finally adopted to following method for troubleshooting my jetting:

Main PJ FAS Clip Setting Observations
122 381-7/82nd Note likes, dislikes, behavior, evidence of condition (spark plug, exhaust residue, etc.)

Change one thing at a time, install a new plug and repeat. After hopefully only a few iterations, a pattern will emerge and you'll be able to determine exactly how the change of one element affects the operation.

 

DC, even though I didn't ask the question I was having similar problems as yourself. I'm at 2500' elevation so maybe I won't go too much smaller with the jets. Thanks for the data, but I'm not looking forward to taking that damn carburetor off again! Anybody know the Kawasaki part numbers for a #122 jet? #38 pilot?

 

I'm 200' above sea level and run with no snorkel, UNI filter, 125 main, KLX300 stock exhaust, no smog junk and the 40 pilot was way too rich. Even at 1 turn out it would idle down and die at stoplights. Back to the 35 pilot and 2.25 turns out and it runs good, might go up an 1/8 to 1/4 turn more to see what it does for decel popping. If you are running that high altitude I'd probably stick with the stock pilot jet for now. If you decide to change it you don't need to remove the carb. Just remove the throttle cables, take the idle adjuster out of the bracket, loosen the carb boot clamps, drain the float bowl, and spin it so the throttle side faces toward the ground. You can get the 4 screws out of the carb bottom this way and change the pilot jet or main jet from here.

 

So how's it running now?

 

FYI, I just pulled the spark plug after making the change in my post above. It's has a nice white insulator with a faint indication of brown to black on the electode. Perfect I think. This setup should be good unless or until it starts showing bad behavior in the future.

 

Trial and error? Hmmm another good reason to have a racer and the head mechanic at my shop to do my jetting, 132-40 and air box lid off, the bike is flawless, no back pops and zero hesitation. Yea I'll leave the complicated stuff to the experts.

 

Of course not everyone has experts on hand (unless they want to pay) and then what would be the purpose of this forum?