The jets are cheap, I'd suggest getting the 38 pilot jet. Here in so cal the 40 pilot jet works well. Yes you adjust the fuel screw back to the leaner setting with 38 then adjust the fuel screw accordingly. Using a flat blade screwdriver bit to adjust works but the kouba fuel screw makes adjustments a one second deal. Make

 

how do I get the other jet screws out ?

last time I pulled the carb , I tried my screw drivers on them and nothing fit.

also what do you think about bumping up the main ... I live in San Francisco its often coldish 50-70

 

You need a JIS screwdriver. Japanese industrial standard.

 

amen!

https://www.ebay.com/itm/Vessel-Mega...n/253248984454

I replace my Kaw carb butter-screws with allen head screws.

Horror - google "care and feeding of keihin cvk carb"
You need to do some research into carb operation if you think you're going to fine-tune this thing by just replacing a couple jets based on some internet jockey recommendations, like from me. Or much better: listen to what klxxter recommended to you. He's spent more time messing with the CVK and then even dyno tuned it! It seems though you don't want to listen.

 

You change the pilot, the needle, and the main jet. It's been well established that the entire jetting range sucks - somewhat literally since a lean engine draws hard vacuum under full throttle. It doesn't matter whether you do the Kawasaki/Kiehin parts or the Dyno Jet stuff. My signature has the link to the information I collected, that both my brother (06) and I (09) used in ours running around 1000 feet elevation.

Here is the areas the various jets affect:



In carbs like the CV, the needle jet (the needle fits in to the needle jet allowing fuel to flow around it) is seldom swapped out. I don't even know if it can be removed. As you might guess from the illustration, the needle affects fueling over the widest range. The illustration is for a regular cable operated slide carb, in those carbs, the slide has a cutaway that also affects fuelling, I don't believe the CVs have the same cutaway. I do know no slide or needle jet change has been listed for the KLXs. Just the pilot, the jet needle (proper name for the needle), and the main jet.

Hope that helps a bit in understanding why it isn't just a pilot jet and main jet. As I said, my brother looked up what had been done over the years for his and I verified it for mine. Neither one of us saw a need to "reinvent the wheel" when others like Pippen did it all and published it on the internet. It has been published on a number of sites and in a few posts here from back in 2006-2007. When you find the same jet numbers in a fair number of places with others vouching for results, it ain't just true because it's on the internet. It has been proven to work. You will find the same thing with KLXter and the Dyno Jet work.

I don't know how many times you need to have this in print in front of you to actually do the job. This is my last time. You clearly can take the carb off and that is the hardest part of the job! Nothing is going to sproing out of the carb barfing out hundreds of pieces. There are only a few moving parts that are loose, and nothing really falls out. Just pay attention to the part about putting the carb slide diaphragm in a cup of hot water to keep it ready to fit back in - it works.

 

I'm on board with changing to allen head screws available at a good hardware store or at Fastenal. Some Ace stores may carry them. Do NOT buy black oxide they will rust, get zinc plated.

 

I just got this off the Dynojet website for kit 2152, since you keep asking where's what

 

Here's a pic of access and how easy it is to adjust the Kouba fuel mixture screw, even when the engine is hot

 

Which main jet you choose should be a determination of what mods you have done. The Dynojet instructions provide you with suggestions on what to do with the mods you have undertaken.
In my case full aftermarket exhaust, no airbox lid, grinded out the flow impending weld bead inside the stock exhaust header to help this 18 hp monster come to life (every little bit helps improve efficiency)
I ended up 40 pilot, approx 2 turns out on the kouba fuel screw, Dynojet 132 main jet (the biggest they offer in the kit) and the clip on the needle set in the 3rd groove from the top and mine started up easily when cold, warmed up reasonably fast since it's so cal, and had way better throttle response and torque/power. I was satisfied with that cheap kit. Until I read about pumper carbs. And decided to get a Keihin fcr35 which improved throttle respouse even more, and I'd say a little more hp since it's a bigger carb

 

"the needle" what do you mean the needle.the thing that comes out of the rubber vacuum ? idk what a needle is ...
I took apart my carb and and remember all the parts but I have about 5 people telling me 50 different things at the same time all using technical terms so I can't keep up.


Im not interested in all this extra info, I just need a simple summarized plan :
so 38 ,39 or 40 pilot jet
and a dynojet 2152 kit b/c it has the bigger main and the needle.
and stock fuel screw on stock settings


='s I should have a little better fuel curve and a better warmup/startup ?


what is the stock main and pilot jet sizes?
what does the dyno jet kit main jet size? looks like I need to buy the stage 2 and the stage 1 ... when Im just interested in the stage 1