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Discussion Starter #1
hey everyone, heres my issue. my wifes '00 7r hasnt been running great since we bought it. if your doing well over 80, it'll work great...but cruising in the 3k-5k rpm range, it skips/stumbles hardcore. now its got ah full D&D exhaust, stage one dyno jet jet kit and ah brand new K&N filter. now if im not that great at carbs...now i followed the instructions with the jet kit. im using 136/138 jets the screws are 1 3/4 turns out (the jet kit says 2 1/2 turns but it wasnt running very well at all) and the needles are set at the 3rd notch from bottom. now if i leave the bike on choke...it will run pretty damn well considering the way it has been. choke or no choke after u get past 5k rpms it screams like hell to redline. it idles fine, no problems...its just in the 3k-5k rpm range that it skips/stumbles like its either over fueling. if someone on here could explain to me what im doing wrong...omg you'd be ah life saver! lol
 

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Which jet kit are YOU using? The stock jetting is 170/180 and the Factory Pro kit comes with 168/178 jets! And if you were to use those jet sizes you'd have to do the float bowl vent mod.
 

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The needles control the fueling in the 3,000 to 5,000 RPM range.If your idle is ok and the top end is fine then your needles can be the only problem. This is assuming everything else is good to go (carbs not gummed up,air to fuel ratio is right,etc...). You'll have to experiment with the needles. My guess (IT'S ONLY A GUESS) is that your needles are not set low enough considering where your mixture screws are at. This means you have too much fuel in the 3-5K step. I'd recommend riding the bike with the throttle held in that rpm range for 1 mile and shut the key off. Coast into a spot you can work,pull a plug and see what it tells you. Then adjust the needles accordingly.
 

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if you run better with the choke on it sounds like you're running to lean. I had a similar problem and found the o-rings between the carb boots and head were bad. ran a lot smoother after I replaced them. You can check for a intake leak by spraying carb cleaner around the base of the carbs while the bike is running. and if you hear a change in idle as you spray the carb cleaner then you've got an intake leak.
 

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EDIT:

You do have the main jets in the right cylinders?

You could try sticking one shim under each needle.
 

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..... 1 3/4 turns out (the jet kit says 2 1/2 turns but it wasnt running very well at all) ..... now if i leave the bike on choke...it will run pretty damn well considering ...
Stage 1 Kit comes with 4 jet sizes, 136/138 is correct for aftermarket exhaust as per instructions, but they do not cross to Kawi numbers, click here to convert, but I would hope you done the Kleen float bowl vent mod.

I am by no way a Carb expert... But I fought Carb issues for a year, then went and stayed at a Holiday Inn Express, Had Jim (WhiteHindrex) on speed dial, and I learned every aspect of the carbs, down to the why... First thing I would do is run compressed air to make sure the valves over the needle-jets are moving freely... I just took a picture off of google images added words, not my carbs.



If they are all 4 moving the same. You are going to have to open up the carbs again on the Jet Side. Measure the Floats, choose your own height from the Searches, I went with Whitey's float height. Take the Pilot Jet out, run a Strand of Wire throw it and soak it in carb cleaner overnight with the strand of wire in it.

My trouble ended up being the nice piece the Main Jets screw into. Part 13091:



Those guys have holes all over them when clean. I had to take a strand of electrical wire looking up into a light until I could see light threw all the holes after a soak over night.

Run compressed Air threw everything you can, and move your (EDIT) A/F screw back to 2.5... Choke means running lean I believe... If you take her plugs out right now, they should be brown from running lean at low RPM...

Just my guess, hope it helps... As others have wrote, make sure you have no vacuum leaks, and a good sync helps amazingly.... Allen
 

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Oh, do the compressed air check with out the bike running. When you move the choke handle, you are actually opening up air passage inside the vacuum valve to assist.... Allen
 

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Discussion Starter #8 (Edited)
I am running a float bowl mod. now the jet kit stated putting the two shims on TOP of the clip of the needles. then the plastic retainer sets on top of them. the bike just had the exhaust, no jet kit, no fliter. the guy i bought it from "started" the float bowl mod and never finished it. so i finished where he left off. didnt seem to help much. so 5 different "bike shops" later the bike still isnt right. everytime someone looked at it...they just cleaned the carbs and said "there that'll make it work better" now as far as i know the right jets are in the right cylinders. 136 on the outter and the 138's on the inner. the floats heights are set at 15mm. http://www.dynojet.com/pdf/2170.pdf thats the instructions i followed. i have a set of 172/182 jets that ive had for a while. i will try everything everyone has mentioned. it does give me a better understanding of it now. if anyone needs more info from me just let me know. thanks everyone!!!!!
 

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Discussion Starter #9
ok, ive just reset the screws to 2 1/2 turns out, ive placed the e clip at the 4th notch from the top ( like the jet kit stated) i put one washer under the e clip and one on top. now the plugs were "whitish" when i pulled them..everyone of them(lean right?) so i just fired the bike up...let it warm up, idle wasnt bad..bouncing from 1100-1150ish..the skipping is almost not even there between 3k-5k rpms now...at about 7k-8k it "crackling"..but that could be the D&D exhaust...i did notice a bit of black smoke out the exhaust when i would rev it...everytime...running a bit rich maybe? im gonna let it cool down and try it again and see how it acts. but im atleast starting to notice a change now. :D since day one i thought this bike was doggy...and i knew that wasnt right...to me it seemed like ah strong 500 ninja instead lol. but i wasnt sure at first if it was because i was used to a 9r. but...this bike just doesnt seem to have the "gotta go" power it should. its too bad cuz this bike has had a hard life from the last owner...been down at least 3 times(hard downs..stunt riding hard)
 

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I'm glad to hear it's going in the right direction for you. Before any more changes are made I would ride it a little to make sure all the black smoke coming out of the engine is not from the previous configuration and you're just cleaning it out. That being said you need to read the plugs in all 3 rpm ranges (idle,mid range and high rpm) to see where you're at with it before adjusting anything. That way you know what you're chasing. Good luck.
 

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Discussion Starter #11
Im thinking the bike just needed to be cleaned out. it doesnt seem to have anymore black smoke. but yes ive gotta run it a bit to see just what its doing. but hey thanks EVERYONE!!! you have no idea how much of a stress reliever this is. I've spent almost $1000 last year to get this thing right..and it never happened. i was worried it was gonna go the same way this year! thanks again everyone! :D
 

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Im thinking the bike just needed to be cleaned out. it doesnt seem to have anymore black smoke. but yes ive gotta run it a bit to see just what its doing. but hey thanks EVERYONE!!! you have no idea how much of a stress reliever this is. I've spent almost $1000 last year to get this thing right..and it never happened. i was worried it was gonna go the same way this year! thanks again everyone! :D
Now get a $65 sync gauge off FeaBay, Carb SYNC here is what I got. It was the last piece of the puzzle. VERY IMPORTANT TO PUT THE WHITE restrictor valves in, start the bike, let her warm up, let the needles just bounce all over the place, then close all the restrictor valves on the test set, and barely open all four. Adjust 1 and 2, then adjust 3 and 4 to the same, then in the middle of 2 and 3, match the all 4... The number is meaningless, but all mine ended up being at 205mb at idle, really neat watching the needles bounce in sync. The Bike ran amazing after that. I just ran a tube from 1 to 2 and a tube for 3 to 4 so that I can resync again before Daytona... The Jury is out if there is an advantage to capping them, or doing what I did, as long as you have no vacuum leak and they are at the same pressure, it will not matter....

One last thing, I would switch to Iridium Spark Plugs now to get a fresh start, a little more, but you don't have to GAP them.

Now find your self a +4 advancer.... Hard to find, but here is the one I won on eBay a few months ago, HERE and in the description it has the part number and other bikes that use the same advancer. Just don't make the stupid mistake I did and forget to drain the oil... Heck, she needed it.... :)

Hope you get her running good... Wrap your fuel lines in header tape while you are in there to prevent the famous Vapor lock that happens at the worst time....

Stepping off Soap Box now...:tard
 

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awesome!! i just ordered the carb sync...so as soon as that coms in, im on it!!
You can also Sync your 9 (EFI or Carb), it will make a difference. Look under the Carbs to see if your wife's #2 vacuum has a bolt in it, or a vacuum line. The kit will come with a brass tube you can use for the sync, or steal one off your 9 if you don't have one, or Google "92150-1161" and buy one (or 2 if the 9 needs one), under $4. It is called Bolt, but it is the vacuum bolt in the Cylinder Head.

Here is a video after putting the Carbs back together all evening/night/AM, and she started on first try (primed fuel bowls earlier by having bike in 1st, no clutch, hold start button til pump stops pumping). VIDEO HERE. I had the idle screw almost all the way in after the rebuild, that is why I had the high idle... But she started right up. Watch the needles bounce, but go smooth when I blip the throttle (at 4 am in my garage)....

See were I put the White Restrictor valves. You leave them open as you start the engine to not trap any vacuum pressure in at start, then close them completely, and open til the needle is just about to bounce before bouncing violently. The video shows how much they bounce before you close and barely open the restrictor valve, and you can see how far off the sync was when I had the butterflies all Exactly at the same spots. 1 is way off of 2....

And here is a Picture after all carbs synced, and idle at 1100, mb at 225, the camera angle makes 3 and 4 look off, but they are all the same.



I just tried to find you an Advancer to finish up with the common mods. I searched and searched, I can not find a plus +4 advancer, I did find a +2 HERE, RTRKAW3102 is a +2, RTRKAW3104 is a +4. Any advance will help with throttle response, I can not find the adjustable one anywhere.
 

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Discussion Starter #15
yea i just went out to start it up, and...ugh! right out of the gate..its running worse. shes back firing like crazy...3k-7k rpms. so i pulled the plugs..and cylinder 1 looked normal. cylinder 2...plug COMPLETELY covered in oil...cylinder 3 looked black and cylinder 4 was wet. i just cant win for losing! it ran good yesterday...to the point i was gonna road test it today.
 

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I knew nothing about motorcycles, just self taught everything from these two forums, and many PMs and calls to Whitey... It took over a year, but my Bike runs amazing, and now I know what to do if the plugs are Carbon fouled or White... I then realized how simple everything truly was... I was lucky no one in Jax would would work on a Carb bike, I too would have spent the grand easy, but then I would have been stuck always going back to the shop... Now I'll pull her apart to just check plugs... Then get the chance to learn lessons learned on the next, and the pattern will continue for the next and next...

But if you do get an advancer, Drain the oil first... I don't know what I WASN'T thinking... Kind of why I am scared to clean my neutral contact as she flashes some days....

Hope your wife is happy brother...
 

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yea i just went out to start it up, and...ugh! right out of the gate..its running worse. shes back firing like crazy...3k-7k rpms. so i pulled the plugs..and cylinder 1 looked normal. cylinder 2...plug COMPLETELY covered in oil...cylinder 3 looked black and cylinder 4 was wet. i just cant win for losing! it ran good yesterday...to the point i was gonna road test it today.
OIL on a plug.... Maybe a piston ring didn't seat, or, you have leaking fuel bowl gaskets, and fuel is leaking down into the chamber and getting past the rings... You need to PM WhiteHendrix, better chance to catch him at http://www.kawiforums.com/zx-7r/ but he is the best I know...

As for the wet plug, do you get white smoke out that Carb after shut down? Could be raw fuel from a leaking fuel bowl float gasket...

I truly think you have a vacuum leak right now, make sure you have a JIS phillips (Japanese industry Standard) to get the boots holding the carbs tight. There is one in the owner tool kit.
 

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Discussion Starter #18
ok i got my carb sync today...worked great!!! the bike is synced...but the popping is still there are 3k-5k rpms. actually its more like a "snapping". i pulled the plugs again...cylinder 1 and 2 are white (lean right?) cylinders 3 and 4 are wet. now cylinder 4 is very wet...compared to cylinder 3. now my question is, how the hell do i fix that lol...arnt they all supposed to be a brownish color? lol
 

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Check your float height, and pilot screw settings. Also make sure the slides are raising up as you rev it and the needles aren't pitted or broken. That's where I'd start.
 

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Discussion Starter #20
im thinking cylinders 1 and 2 are just leaned out from the needle heights and cylinders 3 and 4 might be the float heights are wrong..it its over fueling..
 
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