bogging and hesitation at 12500rpm : Kawasaki ZX Forums: Kawasaki Ninja Forum

gus_chiggins77 · 05-05-2008, 10:03 AM

My 04 ZX6 is bogging and loosing power only from 12500-14000 RPMs. Actually, I can't even really call it bogging. It's really strange, and it only happens at those RPMs. The engine sounds really high pitched during this period, and then recovers when I hit around 14000. I had recently stored my bike for 7 months with a fuel stabilizer. It ran fine for the first few tanks of gas when I started riding it again, but now this. I was going to run some seafoam through it thinking that the injectors may be gummed up from storage, but I can't figure out why it would only bog at a certain rpm.

Any suggestions?

768-Ryda · 05-05-2008, 04:30 PM

have u tried to run some fuel system cleaner to see if that will help

SLIDER · 05-05-2008, 05:01 PM

Quote:

Originally Posted by gus_chiggins77

My 04 ZX6 is bogging and loosing power only from 12500-14000 RPMs. Actually, I can't even really call it bogging. It's really strange, and it only happens at those RPMs. The engine sounds really high pitched during this period, and then recovers when I hit around 14000. I had recently stored my bike for 7 months with a fuel stabilizer. It ran fine for the first few tanks of gas when I started riding it again, but now this. I was going to run some seafoam through it thinking that the injectors may be gummed up from storage, but I can't figure out why it would only bog at a certain rpm.

Any suggestions?

can you describe the high pitch sound it makes. The only thing I can think of that makes a high pitched sound that sounds like it's coming from the engine would be the fuel pump. If the the fuel pump is being clogged or is having some sort of problem it will cause the engine to stumble, especially at high RPM. It could be that the screen on the pump is clogged too.Definitely run some fuel system cleaner through it. Do you have any aftermarket parts on it? Power commander? ignition module? etc...

gus_chiggins77 · 05-05-2008, 11:31 PM

The motor is stock except for the exhaust. The sound I'm describing is the engine itself. When the engine reaches the described RPMs, it sounds like it usually sounds but at a much higher pitch, and with a significant loss in power.
I will check the fuel filter and run some engine cleaner through it.

Scabbs · 05-06-2008, 01:18 AM

could be your valves

SLIDER · 05-06-2008, 12:26 PM

well... I just asked the tech were I work and it's got him stumped. The whole losing power and going high pitched is kinda contradicting. How's the oil look?

gus_chiggins77 · 05-06-2008, 06:58 PM

the oil has about 600 miles on it, so it's getting a little dark.

SLIDER · 05-06-2008, 07:04 PM

when it happens, what throttle position are you at?

gus_chiggins77 · 05-09-2008, 02:26 PM

It will act this way at any trottle position.

I took it out today, and ran a full tank with sea foam through it, and now I'm starting to think that the rev limiter could be malfunctioning. Is this possible?
It's still doing the same thing from 12500-14000, but now the limiter kicks in at 15000 and won't go past it. I don't remember it doing this before.

SLIDER · 05-09-2008, 04:46 PM

well it does sound like an ignition problem, but not necasarily your rev limiter. Is the bike giving any codes? maybe some sort of glitch in the cdi. do you know anyone with the same bike? if you do, try switching the cdi and see what happens. check your plugs, wires, coils, etc. It could be mechanical too.valve adjustment, weak springs causing valve float, flat cam. Start with the basics first. Ignition, fuel, and compression...

I forgot to ask, how many miles on the bike?

gus_chiggins77 · 05-10-2008, 12:49 PM

my bike has 8900 miles on it. Thanks a lot for the advice. I'll keep you posted

dumped_it · 05-10-2008, 11:56 PM

well it is a Kaw.they have prob

SLIDER · 05-11-2008, 09:09 PM

Quote:

Originally Posted by dumped_it

well it is a Kaw.they have prob

to be honest, I think you got a lemon. I've had a 636 that I wrecked and literally broke the front end off. It ran without the front half of the frame with no problems. I've tumbled my 07 ZX6R down the road at 70 and 20. Not to mention the 50mph low side that I had today. Kawi's are pretty bullet proof. Every manufacturer produces a couple bad bikes now and then.

gus_chiggins77 · 05-11-2008, 11:34 PM

Don't worry, I'll do what I have to to fix it. I love this bike!

Scabbs · 05-11-2008, 11:45 PM

what did they say?

Sev · 05-13-2008, 04:11 PM

Doesn't the exhaust valve start to close off a little at 12500rpm? Is the motor set correctly?