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ZX12 2002 power flatlines at 9,000rpm? Any ideas ?

16K views 24 replies 14 participants last post by  Ej4good 
#1 ·
Hi all again, back to the fold (had the 2000 model when they first came out - sold it since the kiddies came along, now bought an 02 model cause I just can't be without my 12.)

Anyway, I've just bought this 12 2nd hand, it has 23,000k's (14,000mi) in great condition except... When I've now finally opened it up above 9000rpm I find the power just flatlines... theres still heaps of power, just nowhere near the rush that usually starts around that RPM range..

By Flatlines I mean it doesnt increase at all, and it doesnt feel smooth in case your wondering if the last owner modded it to produce all power down low.. on that thought I'd say its not a rev limiter either since it kinda surges and very slowly builds up RPM, just with nowhere near as much power as it should have.

I've ordered the compulsory K&N air filter for it, I'll pickup new plugs (which reminds me, this site favours the CR9EK-PA plug (CR9EKPA for searches) but theres now the iridium plug of CR9EIX available as an alternative, anyone used this?)

Anyway, back to the issue... have you any thoughts whatsoever on this? I'm thinking it would be air related (reason for the K&N) but anyone else have any thoughts?

Note: I havent yet checked the plugs, but I'm sure they're due for a change anyway (Id like to know the basics are all of good quality and working order anyway), oil I havent changed -but will this weekend- although the dealer said they gave it an oil change (and since I rode it without checking the oil clarity I can't be sure now as it would be dark oil already), and I've gone through two tanks of fuel from different sources with the problem existing in both fuels. No Power commander is installed, but I cant be sure if it ever was the only mod was an alarm which was taken off before sale (only noticed that since the rear indicators were spliced into I guess for the flashing of the indicators on arming/disarming)

Any thoughts???

Thanks all
JasonBW - Sydney, Australia
 
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#4 ·
Hi Boosta, yep, it does keep going, albeit slowly (not accelerating hard like it should) I think if the clutch was bad it would freewheel faster than normal revs under acceleration, but this prob has the revs increasing slowly. That sound right? Just a bit more info, it doesnt matter if the throttles wide open or slightly open, it accelerates the same over that rev point.

NONBELIEVER, good point, but when I read posts saying guys change their plugs every 15,000mi, v's posts saying they're good for 100,000mi I figure its a better be safe than sorry, especially when coming across this prob if its spark related then it'd solve it. (I intend on fixing it, and WILL post the resolution up as a searchable item for others in the future)
The exhaust is standard, how could that be the problem since its all stock. I had a full Akro system on the 00' 12, was great but I need it quieter now.
 
#5 ·
jason... check the simple things.

Plugs should not need service that early in the bikes life if the mileage is correct.
The stock plugs are $18 us EACH...

If the bike is low on power... Id check valve clearances first. If the plastic cover is still installed.... 99% chance its NEVER been checked.

Also look at the clutch. The factory offsets the last fiber. You should align it and measure the stack height according to the manual.
 
#7 ·
NONBELIEVER said:
jason... check the simple things.

Plugs should not need service that early in the bikes life if the mileage is correct.
The stock plugs are $18 us EACH...

If the bike is low on power... Id check valve clearances first. If the plastic cover is still installed.... 99% chance its NEVER been checked.

Also look at the clutch. The factory offsets the last fiber. You should align it and measure the stack height according to the manual.
Goddamn. I must have fallen asleep for a year and a day.

NinjaEd has actually followed through on mailing the iPod and NB is downright congenial above.

Go figure.
 
#8 ·
Thanks nonbeliver, I'd have to say simple doesn't exactly spring to mind when checking valve clearances... for me anyway.. :)
Thanks for the info though, what do you mean by the plastic cover?

US$15 is the price we get the iridium plugs for, thats not too expensive if it helps in either eliminating one thing to worry about or even fixes the prob (ok, I'm starting to doubt it would now but theres still a chance one could be failing at high revs). I'm dreading the thought of the cat being blocked like Vinne said, wonder if that can be checked easily?

I'm not exactly a mechanic, I mean I'm fine to work on a bike to the point of pulling it apart entirely and putting it back (built a couple of track bikes that way), just never opened an engine up since stuffing up an XL250 engine when I opened it as a kid :) Engines make me think twice.

I'll check the price at the local dealer to get those clearances checked, if its too painful then its prolly about time I learnt some confidence in taking the head off an engine.

Thanks all for your thoughts, if you think of anything else to check just yell out.
JasonBW
 
#9 ·
Its hard to offer advice on a website on a sick bike, Its hard T/Sing a bike sometimes right in front of you.

But if I understanding you correctly the symptoms sound like you have a coil stick going bad. When they start going bad you get the symptoms of bike not reaching redline and missing at high RPMs,

Doing a quick check of your plugs may determine which coil stick is bad.

Also another symptom is its not as bad when bike is cold. But when it warms up it gets worse.
 
#11 ·
I had this exact problem on my 02 and the dealer searched and searched replacing almost every electrical part (including upper and lower wire harnesses) and in the end.....it was the fuel filter(or pump, I can't remember) in the tank. Sorry I don't remember which it was but what ever is in the tank because they figured it out by swapping a tank from another bike. Hope that helps.
 
#12 ·
Outstanding - Thanks James !!! I'll be sure to check that if what I found didnt fix it...

What did I find ???

oh yeah, this is good, I stripped the bike in prep to change the plugs and check valve clearances, thought while its apart I'll do the Kleen air mod, start the mod, get to the part where I pull the kleen air vaccum thingo out, did that, had it in my hand when reading the next step which was to block off the vaccum line that went to the kleen air bit, it was already blocked by a home made crimp job with strong wire (but left attached to the kleen air thing!! weird)

Then found the airbox has already been sealed with silicon, and the crankcase air was run already as per mod, with the exit point behind the tank blocked off too...

So.. the guy who owned it previously to me had 1/2 done the job.. no idea why.. but the crankcase breather hose had been left unattached and unblocked.

That would cause vaccum problems right? that would also be a reason why the motor just seemed way loud for stock... and why idle is a bit rough.. and maybe... just maybe :) the reason why its shitting itself above 9K rpm... hmm.. I guess a test ride will tell... just need to wait a few days since I'm off to another city tomorrow for a stint.. bad timing.

Will write back once I ride it... thanks all for the input!

JasonBW
 
#13 ·
i'll give you a little advice while i'm in this thread:

regarding the iridium spark plugs - they are way better than the factory platinums...

despite only having 12,000km of easy riding on the stock platinum plugs and them being totally clean when checking them (they looked brand new) i still bought some iridiums and put them in...

STRAIGHT AWAY i noticed a massive difference...a bit smoother idle but the real noticable thing was the way the bike revved and how smooth it was up in the higher rev range...it just seemed STRONGER...

i only paid about $16 or so each from my local dealer for these plugs...money very well spent...

summary: these iridiums are great and i will never go back to the platinums, i don't care how long they are "meant" to last, the fact is, newer technology and NEWER plugs will always be better (same manufacturer)! :wink:
 
#14 ·
Thanks Bluedraco, mine were only $21 ea, not bad for Australian $$$. Looking forward now that I'm home to assemble the 12 and test it all out.

Bloody torque wrench packed it in.... borrowing a mates to do the plugs.. it'd have to happen now wouldn't it :)

Thanks
JasonBW
 
#15 ·
FIXED- ZX12 2002 power flatlines at 9,000rpm? Any ideas ?

ALL FIXED (re-posting so the fix can be found for others doing searches)

Turned out james_otsr was right on the money, the Fuel Pump wasnt pumping enough at the high revs to supply demand!

Swapped for another 02 model pump and hey presto, instant GRIN.

Thansk all for helping too!

JasonBW
 
#16 ·
Re: FIXED- ZX12 2002 power flatlines at 9,000rpm? Any ideas

jasonbw said:
ALL FIXED (re-posting so the fix can be found for others doing searches)

Turned out james_otsr was right on the money, the Fuel Pump wasnt pumping enough at the high revs to supply demand!

Swapped for another 02 model pump and hey presto, instant GRIN.

Thansk all for helping too!

JasonBW
So I guess that what my problem is too! Just like everyone lead me to believe. Thanks for confirming - I was having the exact same problem. Especially after longer rides, or when it's hot out.

I need a muzzy pump..........
 
#17 ·
GOOD STUFF, I can get you in touch with a couple of US contacts who were ready to sell a pump for only $100 - dog cheap ! (Ended up buying one local in Australia for the same price)

This is for an 02 and upwards model.

Want their email address's?

P.s. Glad this helped, shit hot forum this is, the people make it so.
 
#20 ·
Re: FIXED- ZX12 2002 power flatlines at 9,000rpm? Any ideas

jasonbw said:
ALL FIXED (re-posting so the fix can be found for others doing searches)

Turned out james_otsr was right on the money, the Fuel Pump wasnt pumping enough at the high revs to supply demand!

Swapped for another 02 model pump and hey presto, instant GRIN.

Thansk all for helping too!

JasonBW
Glad you got it fixed. Took my local shop 60 hrs in labor and who knows how many parts to find it, gotta love extended warranty :)

james
 
#21 ·
Hi Wedriverzs this one was stocker, I dont have a Power Commander so I really had to stick to stock.

James_otsr, what is this extended warranty? I'm DAMN glad for you that was covered, that bill would have been freaky!!!

I still am in awe over this forum, great people, smart people damn this works ! Thanks all for sharing the knowledge... p.s. if you happen to have benefitted like me then maybe just pop a couple of $ to the paypal link on the main page, sure as hell this site saved me a load so I intend on keeping up the paypals each time it helps (no doubt many in future)

Like he says dont feel obliged..
Heres the link anyway:
http://www.zx-12r.org/WebsiteContributions/PaypalContribution.htm

JasonBW
 
#22 ·
jasonbw said:
James_otsr, what is this extended warranty? I'm DAMN glad for you that was covered, that bill would have been freaky!!!
JasonBW
Yep and I've still got til next summer on it :).

That's actually nothing in the big picture.

August of 2004 started with a seized motor, then the problem I mentioned, strange oil leak they couldn't find for a while, and now its back in with a cutting out problem that they can't figure out. The bad news is I think its been in the shop a total of 4-5 months (and counting...) since then. The good thing is I haven't paid for a thing and now have a 2002 with a new motor, ECU, upper/Lower wire harness, all new sensors, new throttle body with TPS, and who knows how many other small items.

oh and a big +1 to the site too, thanks Easyrider!!

james
 
#23 ·
I had the same problem with my 04 zx12r, I replaced clutches, spark plugs, ignition coils, cleaned my bmc filters, new fuel pump and after all of that I still had the issue. Finally went to the shop and the mechanic cleaned the sock and the filter down in the fuel pump housing. Now is back to business, I'm back in love with my bike!
 
#25 ·
Jason,
I have a 2002 Kawasaki Ninja ZX12R and haven’t had the type of problems you are having now, but when I bought mine, I tore it down to the frame and overhauled it completely. Not sure if it was needed because it only had 8,000 miles on it, but I did it anyways and she runs like the Roadrunner on Cocaine. Might help with RPM issues…

Eric
 
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