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Discussion Starter · #1 ·
I've only had this bike for a couple weeks now and the previous owner had the tuning waaaaaaaayyyyyyy off....I've been getting things running right, now just need a carb sync...Is there anyone in the Elmira NY area with a Carbtune or similar tool that could help me with this process or inform me of another way of doin this on the cheap...Im broke right now, but want the bike to run better
thanks
 

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Did you try bench syncing it? You can get it pretty close visually when the carbs are off the bike and just sitting in front of you. There are 3 small holes in the bottom of the carbs- right where the butterfly valve meets the body. You want to adjust the butterflies to they are all exactly covering the first half of the hole.
 

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Did you try bench syncing it? You can get it pretty close visually when the carbs are off the bike and just sitting in front of you. There are 3 small holes in the bottom of the carbs- right where the butterfly valve meets the body. You want to adjust the butterflies to they are all exactly covering the first half of the hole.
And at the end of the day that can still result in huge differences. You can build a manometer with some tubing and ATF. Google dat shiz.
 

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Carb synching will only help your idle, you won't really notice a difference at anything above that according to an old timer who owns a local kawasaki shop in Southwest, MI.
I have a carbsync I'd let you borrow if you want to PM me.
It is super easy to do; you need a phillips head screwdriver, the carb sync, a remote gas tank and about 10 minutes of time.

Have you had the valves adjusted or anything recently? That is usually what promotes a carb synch. If you haven't, I would recommend it; also something you can do yourself.
 

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I have a question to add to this post, I have a 96 ZX9r with 11,xxx miles on it. I stay on top of the maintenance and ride it regularly. Two years ago I broke the carbs down for a good cleaning and it purred like a kitten after that. All the seals and rubbers were intact. I recently noticed the bike won't hold a good idle either(dips down to almost a stall). I'm assuming its the carbs that need a syncing, I have the gauges and am going to do it this weekend. My question is whether to start with the air pilot screws first since when I rebuilt the carbs I returned the pilots back to a standard four turn out point, I never touched the sync screws, so what would've changed in that department? The only other thing I can think of is I never replaced the plugs over the pilot screws, could this be causing an air leak and throwing off the sync or should I stick with strictly adjusting the sync screws? P.S. I'm going to do the valve clearance this winter so I didn't want tear into that yet.
 

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Carb synching will only help your idle, you won't really notice a difference at anything above that according to an old timer who owns a local kawasaki shop in Southwest, MI.
I have a carbsync I'd let you borrow if you want to PM me.
It is super easy to do; you need a phillips head screwdriver, the carb sync, a remote gas tank and about 10 minutes of time.

Have you had the valves adjusted or anything recently? That is usually what promotes a carb synch. If you haven't, I would recommend it; also something you can do yourself.
10 minutes?

Never mind the time spent taking off the tank and airbox. How you manage to get that whole process down to 10 minutes is beyond me.
 

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Four turns out is pretty rich. I think stock is like 1.5 turns out. I have a full muzzy exhaust and aftermarket air filter, and I'm currently running 3 turns out on the pilot air screws.

I don't think anyone reinstalls their drilled-out pilot airscrew caps once they are removed. That shouldn't make any difference....unless one of the little pilot airscrew o-rings is missing. That would definately cause a problem.

I tried to do a "bench" synch. Didn't work for shit. So I built my own manometer for about $5 and it works just fine, only has two channels tho, not four, so there is a little more monkeying around.

How often do you ride your bike? Do you put additive into the fuel to keep it fresh?

I would suggest another carb cleaning before a synch.
 

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I was wrong, I had the screws out three turns. I went back to 2 turns and synced the carbs, they were off and it seemed to help but the idle still drops low after coming off the throttle. I think I'm going to try 2 1/2 turns or 3 again and resync again, to see if it gets better. I didn't seem to have any issues until the weather got hot. I'm wondering if it is the less dense air causing a rich condition? Also, The bike seems flat in the midrange and really hits at 7500 rpm, should I try raising the needles one more groove. I installed the dynojet kit per the instructions. To me the bike does not seem to be living up to its potential. I use stabil in the winter but during the summer I burn a tank a week of 93 octane so I don't use any additives.
 

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Discussion Starter · #9 ·
Carb synching will only help your idle, you won't really notice a difference at anything above that according to an old timer who owns a local kawasaki shop in Southwest, MI.
I have a carbsync I'd let you borrow if you want to PM me.
It is super easy to do; you need a phillips head screwdriver, the carb sync, a remote gas tank and about 10 minutes of time.

Have you had the valves adjusted or anything recently? That is usually what promotes a carb synch. If you haven't, I would recommend it; also something you can do yourself.
I haven't adjusted the valves...but I have a feeling that they need to be dealt with before I sync the carbs...there is a noise in the top end and need to have that addressed first then do the sync...no point in doin it twice.....i hate weird noises and this is the first bike ive owned so ive been learning alot
 

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I was wrong, I had the screws out three turns. I went back to 2 turns and synced the carbs, they were off and it seemed to help but the idle still drops low after coming off the throttle. I think I'm going to try 2 1/2 turns or 3 again and resync again, to see if it gets better. I didn't seem to have any issues until the weather got hot. I'm wondering if it is the less dense air causing a rich condition? Also, The bike seems flat in the midrange and really hits at 7500 rpm, should I try raising the needles one more groove. I installed the dynojet kit per the instructions. To me the bike does not seem to be living up to its potential. I use stabil in the winter but during the summer I burn a tank a week of 93 octane so I don't use any additives.
What is your idle at? Manual says 1100 +/- 50 rpm IIRC. The dropping of the rpms is most likely due to float bowls being gummed up. If the power comes on late in the powerband, this means your float bowls might be sticking shut or less than fully open. Powerband should start about 6k.
 

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I haven't adjusted the valves...but I have a feeling that they need to be dealt with before I sync the carbs...there is a noise in the top end and need to have that addressed first then do the sync...no point in doin it twice.....i hate weird noises and this is the first bike ive owned so ive been learning alot
Kawasaski's are known for louder than normal valvetrain. How many miles are on the bike again? Odds are it has never had a valve adjustment which could be another reason your power is late.
 

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I did pull the bowls and everything was clean and gum free. Floats operate without friction. I reset float height to factory specs, only one was a little off. I did notice the float valve rubbers looked as if they were pulling away from the needle(the bottom of the cone), don't know if its normal or the dreaded shrinkage talked about on the Factory Pro site. Does anyone have personal experience with Dynojet Stage one kit on a 1996 zx9r? I did a search and nothing comes up.
 

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I did pull the bowls and everything was clean and gum free. Floats operate without friction. I reset float height to factory specs, only one was a little off. I did notice the float valve rubbers looked as if they were pulling away from the needle(the bottom of the cone), don't know if its normal or the dreaded shrinkage talked about on the Factory Pro site. Does anyone have personal experience with Dynojet Stage one kit on a 1996 zx9r? I did a search and nothing comes up.
do you mean the diaphrams? These must seal at the top or else they won't work properly. Vacuum causes them to lift, and if there's a leak there's no vacuum and they won't lift.

I have a dynojet kit in my zx9 (1995) and it is my belief that these carbs are very sensitive to float levels. I live at sea level and have come down in main jet size cause it was running to rich. DJ 185's now, but still testing. May come down again after I run the bike for a bit.
 

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Have you noticed a change in power since going to the smaller jets? I have broken down the carbs and found the screen on the the float valve almost completely covered in debris, also the number 3 cylinder had some debris, which is strange as there is a fuel filter just after the pump, I can't figure out where it is coming from. I screwed up the brass valve bodies while pulling them from the carb body so I ordered a rebuild kit with new float valves and new pilot o-rings, and gave the carbs a good cleaning. I'm going to shim the valves while I have it apart and also change the fuel filter. I'll update on progress as parts arrive.
 

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Also, anyone know what size carb adapters I need to sync, my sync gauge came with a set but they were too small, I'm guessing they are 5mm, I'm also guessing 6mm might be the right size?
 

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Kawis should have nipples on the bike already.
 

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My butt dyno says the power went up after reducing the main jet size.

I had to add two more nipples to synch the carbs, only had two to start with. I don't remember the size, sorry.
 
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