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need help carb tuning !

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bike specs

installed a the DJ-116 main and the 38 pilot with the DJ needle. 

tried 2 turns out, 2.5 turns out and 3 turns out

stock airbox, new filter, new plug, stock exhaust, EPA stuff removed and plugged 

oil levels fine 



take note:

1) installed a mixture meter and mixture is in a good ratio during the ride and most of the time

2) with 2.5 and 3 turns out I get 11.5-9 rich during idle 



heres the problems  

3 or 2.5 turns out

the throttle doesn't feel smooth on 3 or 2.5 turns out. I know thats vague, its hard to explain ...almost feels as if you removed oil from the motor and drove it ...almost like knocking heavy vibrating

it happens when I'm going up a hill doing heavy throttle

only happens when I'm riding not at stationary reving  


2 turns out

when I run it on 2 turns out it runs nice and smooth  BUT its really hard to start up

...I know the mixture screw doesn't affect heavy throttle while riding , thats why I'm confused as to why it goes away when I turn down the fuel 





not sure what I should do , could it be something with the float? 

took it to a mechanic they said it sounded normal they dont think they drove far enough to produce the noise 

they suggested it could be the chain 

2.5 turns out was recommended by kawasakiforums members

sounds right but I'm running rich at idle so maybe I need to go down or should I just go back to the stock pilot jet?






Edited by horrorfan
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I drilled my air box, removed the air box lid, installed a Four Stroke Works header Pipe, put on a FMF muffler and installed an aftermarket needle and jet kit. With all this done I kept the same pilot jet. Everything ran pretty good for a vacuum slide carb. When it was time for a rebore I put on a Bill Blue 331 kit. Thinking this would call for a step up on the pilot jet I put in the #38. Never could get it to come off idle smoothly. I went back to the #35. I worked with the stock needle position and was able to get it come off idle really well. One thing I did was mark the needle jet/bleed pipe so when I screwed it in it was in the same position each time. This insured the needle set in the same position in the needle jet/bleed pipe each time I changed jets for the altitudes I rode in. By experimenting with the the needle position up or down I was able to tune it to where the motor was very responsive regardless of the altitude. Each bike is different so you have to experiment until you find the sweet spot. The level of your idle speed can also affect how the bike comes off idle.  Hope I am not preaching to the choir here. Keep us posted on your progress.

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Under heavy load full throttle, you are just running on the main jet, sputtering or bogging is too rich, skipping and backfiring is too lean. I think your main jet is too rich. One way to troubleshoot rich/lean jetting is to lightly feather the choke when warm. If you feather the choke on and it gets better you need more fuel, if it gets worse you need less.

2.5 turns out is quite a bit, 3 is a lot, I think you have a jetting issue. I would not touch the float until you have beat the jetting to death first.

What bike/year and what is your altitude?

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