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I recently purchased a 2000 classic 1500 and absolutely love the bike. It has low miles for the year (19532) and has been taken care of from what i can tell. no dents or dings and in really good shape.
It has v&h exhaust that has been installed but the problem is that it is running way to rich. if the bike is idling in my garage the fumes will make your eyes burn. i did remove the right air cover today and started the bike to have a look in the carb. and there is a lot of fuel moving through there. the bike idles fine. Its just something that i am not familiar with but, i know its not supposed to be that way. Any help will be greatly appreciated.
 

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If I had to guess I would check to see if whoever did the pipes did jets too, and went with ridiculously oversized jets. Also check to see if the air filter is stoc or high performance like a K&N.

You might check the idle mixture screw and see how many turns out it is. Ideal is 1-3/4 -2-1/2 turns out. If you need less than that, and the bike bogs down at acceleration, the pilot jet is probably too big. If it stumbles at acceleration, the pilot might be too small. Likewise at the top third of the throttle range- a steady cruising with a boggy feeling is probably too large a main jet. Popping or stumbling is probably lack of fuel and needs a bigger main. I usually start with 2 number increases for every change- so if i did pipes, air and jets, I'd jump up from a stock 138 main to a Keihin 142 or 146. Pilot I'd go form a 42 to a 45. Small changes can make big differences, and bigger is not always better when dealing with carbs. What we want to try to achieve is just big enough. My bike now has straight pipes, jets, and a Baron's Big Air kit and I get about 44 MPG with it.
 

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Patrick thanks for the advice. I do know that it has stock air but i am unaware if the jets have been changed or not. I am going to assume that the carb has to be taken off the bike for the changes that you mentioned. I have also read some post that recommend putting in a ez-just pilot screw. is this something that you would recommend? And how will i be able to tell what size jets are in the bike now? sorry for all the ?'s but never messed with this type of stuff before.
Thanks for your help
Ken
 

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Patrick thanks for the advice. I do know that it has stock air but i am unaware if the jets have been changed or not. I am going to assume that the carb has to be taken off the bike for the changes that you mentioned. I have also read some post that recommend putting in a ez-just pilot screw. is this something that you would recommend? And how will i be able to tell what size jets are in the bike now? sorry for all the ?'s but never messed with this type of stuff before.
Thanks for your help
Ken
Jets should have a number stamped on the side of them. Unfortunately, different manufacturers use different numbers for the same jets. Thus, a stock Keihin 138 found in these Keihin CVK40 carbs is a 128 from Dynojet and a 120 from Mikuni. In my bike, I went with a 45 pilot jet (and I did buy an EZ just screw- makes life a lot easier) and I went with a 142 Keihin main jet. But I tried s 140, I tried s 146, I tried a 152. 142 is the best for my bike. Also, unfortunately. it's a lot of trial and error. There is no "one size fits all" when tuning a bike. Each bike is unique, each rider rides differently. Where you live- the geography, altitude, humidity, all have an effect on tuning. And it can depend on what you want more- decent mileage or a hotter performance. There is a sweet spot in there that is a compromise between the two, but where it is is different for every bike. If I could do it all over again, I'd have gotten a FI model. A lot less problems and variables.


As Mr Fair indicated, the plugs will tell you a lot- black can mean too rich, ashy white/grey too lean. They should be about the color of coffee with cream in it.
 

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Discussion Starter #8
Mr.Patrick, so I pulled the carb today and found a couple of things. First the pilot jet is a 45 and I couldn’t find any marking on the main. The fuel air screw was out three turns which I reset to two. After putting everything back together it idles fine and doesn’t seem to have near the fuel flowing into the carb while idling so I’m good with that. However after reading your earlier post I run the throttle up to about two thirds and it seems to bog out because of the amount of fuel. Do you think that this could be that the main jet is to big? Thanks
Ken
 

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Those plugs look a little dark, indicating a rich condition. Bogging, or feeling sluggish at acceleration, often meant too much fuel. If it stalls and pops or bangs, it's likely too lean. You just have to experiment. But I would comfin my changes to,one thing at a time, because if you change more than one thing and it either works better or worse you won't know which change is the cause.
 

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Those plugs look a little dark, indicating a rich condition. Bogging, or feeling sluggish at acceleration, often meant too much fuel. If it stalls and pops or bangs, it's likely too lean. You just have to experiment. But I would confine my changes to one thing at a time, because if you change more than one thing and it either works better or worse you won't know which change is the cause.
 

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1. What did you do to the carb when you had it apart?
2. Are the throttle tests on the road or the sidestand?
3. Plugs are showing rich.
 

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Discussion Starter #12
All I done to the carb while I had it pulled off was readjust the fuel air screw to two turns out and pulled the bottom of the see what the size of the pilot and main were. The throttle test was on the kickstand. There still seems to be fuel coming up from around the main needle while the bike is just ideling. Pulled the top of the carb and checked the diaphragm and the main needle it has the c clip on the 4th notch counting from the bottom. To my surprise there are two shimm washers that were on the top of the needle above the c clip.
 

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I recommend a tear down, cleaning, inspection, replacement of any suspect parts. Inspect needle and seat, check float for being a sinker, all rubber parts, then perform all adjustments to Kawasaki specifications.
You do not want to mess around with jets, etc. when the carb may have a mechanical issue or you will dig a hole very deep in a hurry.
 
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