Hi folks,

I'm kinda new to the forum, but had my 14 from new, which is now 5 years old. It's a 2009. Until last year, the bike was great, no issues..well, not apart from the horrendous clunking gearbox!! Over the last year, I've noticed I have a flat spot between 3-4k rpm...hit 4k in any gear and it takes off. I've had it into Kawasaki, they originally thought it was the petrol tank pressurising and stopping the fuel, so they stripped and cleaned the petrol cap...no change what so ever, but now when I open the tank there's no big gush of air.

I then decided to see if I could sort the problem myself...I've had bikes for years, but the last "modern" bike before the 14 was my trusty old Gpz900, which I've had 23 years, so I've not really worked on anything this new before.

That said, manual in hand, I started with the obvious...changed the spark plugs, Iridium, previously changed 3500 miles ago, so should still have had plenty life in them. Checked the stick coils, resistance within the limits on primary and secondary...pulled the fuel pump out, found this appears to be a sealed unit, so took it to Kawasaki again and they stripped it for me. Showed me the fuel filter inside it, which seemed quite dirty, so this was cleaned as there does not seem to be a replacement part you can just pop in...

Anyway, still got this flat spot between 3-4k and it's starting to drive me nuts. Anyone had anything similar and found how to cure this?

Cheers

* Last updated by: malky1400 on 9/21/2014 @ 12:22 PM *

When was the last time you changed air cleaners? Not blew it out, changed it?

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I put a K & N in at the start of this year, but I was already getting this problem at that stage. Kawasaki have checked if there were any faults recorded, nothing. Apart from the filter, that's the only change I've made, it's still got the std pipes. I'm also starting to feel it surge when I'm changing gear and going back on the power. It also seems to get worse the longer the run...so, for example, I did about 140 mile today, but the last 30 or so were very jumpy on the throttle and actually felt like it was losing power...definitely not as crisp as it was when I went out at the start of the day.

Is this a euro bike with an 02 sensor?

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Yip...I wondered about the throttle position sensor, but again Kawasaki say everything appears ok and can find no fault. Could the O2 sensor be at fault? I'd heard there is a bypass kit I can buy for about £15, but I thought these can only be used if fitted with a power commander.

Na, not the TPS. Last 30 miles it starts in? See wet I'm saying? TPS reads what position is the demand? So from 0 to 100 for argument sake, where is the stumble all up and down with 110 miles at it. It's just reading numbers open and close say.

Back to the 02 and if I have to choose a fuel metering device throwing stumble @ this certain rpm, it is spitting out watt is thrown at it and since this meters a fuel trying to keep from spitting and coughing, how much moisture does the bike sit in? Are you on the wet side of this earth kind of climate?

That kit is a limp. If the throttle shows no position, look at the code page and see where it says a-N and DJ at the 02 and TPS. Don't go there. Instead, do this: if we disconnect the 02 connector, we are going to receive an error code and that says the 02 and bing, we are in 'Method.' We now ride the bike and see if the stumble is gone? If anything, this should be more of a test at the 02 without buying one to find out.

Other than that, how could compression fall off the last 30 miles, it's not compression.
Other than than, how could spark not be there but keep sparking and has no clue about the last 30mi.
Other than that, how about we are down to fuel and take a stab at a fuel sensor so I can pull another one out the ass I have no other place to go.

Only your disconnect knows for sure.

* Last updated by: Hub on 9/21/2014 @ 3:15 PM *

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Wait a minute. Is this fuel stumble or air lag?

I'm stumbling fuel at this rpm range and it cleans up once I hit 4k.
I am feeling this lag of get up and go. No, not like I'm smelling fuel a lot, nor is it bucking like I keep adding throttle and it gets worse. No, it still has a clean opening transition and not fuel in a way.

And again, moving that sub or throttle sensor is going to pop [a code] right out of range it's that tight in tolerance.

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Thanks Hub...as much as I appreciate your help here, I'm not quite following what you're saying 100%. Let me recap on what is happening...

I start the bike from cold, run it for the first mile or so to heat things up, then start to use the power.

If I sit just on 3k in any of the top 3 gears and give the throttle an 8th of a turn, it bogs down slightly, continues to pick up power, but feels restricted, but as soon as it hits 4k, it very quickly clears and gives a GOOD kick in power. This power is then there the full range of revs from 4k and above.

I changed the air filter to a K& N AFTER I'd already experienced this problem, in the hope that this would clear it, it didn't. Since then, I changed the spark plugs with new iridium ones, the old ones had only covered 3.5k miles and when looking at them, the colour and gap was all good.

I checked the resistance on the stick coils, both primary and secondary, again, all within the range specified by Kawasaki.

From there, I removed the fuel pump, had it stripped by Kawasaki, who showed me the fuel filter inside, this was quite dirty, so this was cleaned and the pump built again. This did make a difference to the entire rev range, but the flat spot was still there.

I've ran a full tank of petrol with a 400ml bottle of forte injector cleaner, no difference. Implying that the fuel system was not at fault.

If I keep the revs above 4k, it goes like a bullet. It appears to get worse as the heat builds, telling me it could be a breakdown of something, which leads me back to the stick coils. I'd read somewhere that if these are checked cold, you get a good reading, but if checked hot, this can show a low resistance. I'd considered stripping them off the bike again, removing the rubber sleeve and popping them in the over for an hour to get them up to a reasonable temperature before checking them again...or would this be a waste of time?

Kawasaki have had the bike in a few times now, first time, they felt it was the petrol cap causing extra pressure, so stripped this and cleaned it, no whoosh as you open the tank now, but still no change. I then left it with them, the mechanic test drove it, could not find a problem, so the manager then went out, again never experienced exactly what I was describing, but did say that at times it felt when he put the power down that it felt like it was in too high a gear.

So, just on the gear thing...if I sit at 30mph in top, it's only showing about 1.5 - 2k...I can wind it open from there and go right through the 3-4k spot with no hesitation at all, all the way up to whatever speed I want...the problem is if I'm sitting at between 55-75mph in top and want to wind it on, the power is not there...it bogs down, accelerates slowly, hits 4k then takes off.

Hub - you asked about the climate, I'm here in the UK, I tend to drive more in dry weather, but this problem is here all the time, no matter rain, sun etc...

Cheers

If I sit just on 3k in any of the top 3 gears and give the throttle an 8th of a turn, it bogs down slightly

Not sure if a euro model has this heavier lag than say a western ECU. I'm no longer going after parts, but map patterns instead.

... continues to pick up power, but feels restricted, but as soon as it hits 4k, it very quickly clears and gives a GOOD kick in power. This power is then there the full range of revs from 4k and above.

Look at WOT you are saying. I have power past 4k. I have no spark, no fuel, no sensor, or fuel pump problems per say. Look how the bike responds after 4k. Look at how the bike starts = Instantly.

Trying to narrow it down, I see gears that lag in that area. I see 3 gears in a lagging situation. If we shift with higher rpm's are we cleaning up that 3-gear lag window you place yourself in? Are you falling back into some routine that, oh look, here comes that problem and the gear I'm in.

You can mod the gear position sensor and wire up a hack or buy the plugin from Ivan's Performance, see if that changed things? After 4k there is no problem with the bike. Under 3k, we start pointing to the rider and 3 gears in so many rpm's, because they way you describe how the bike runs, I can't tell if the PAIR needs cleaning is now stabbing for guesses.

Does that kind of explain how you can't find this air lag, or may have induced this lag? Your shift pattern may have evolved into what you are feeling now? I'd have to out and out ride it to understand what you feel is different. If I rip thru every gear and no lag, see WOT I'm saying?

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Hey,

I have 2009 european model. o2 sensor works only 4-6th gears .. not 1-3.

If I understand correctly you can just unplug that sensor and get tested like Hub said .. you get only FI warning light but bike should work now without o2 sensor , i do not known is map same than 1-3 gears in this way but should work.

I have PCV + o2 optimizer , but you do not need both at the same time .. optimizer works alone too and change AFR 14,7 --> 13,6 in closed loop.

I've made the mod how can I get 2nd gear in display by the switch when i want and get rid of closed loop.
However, the optimizer seems to work so good that my "assdyno" do not feel any extra power thisway.

I'm not sure whether it is acquired without PCV.

"So, just on the gear thing...if I sit at 30mph in top, it's only showing about 1.5 - 2k...I can wind it open from there and go right through the 3-4k spot with no hesitation at all" ..... probably due to the the difference effect of IAP map than 55-75mph.

o2 sensor works only 4-6th gears .. not 1-3.

My understanding is the 02 is the same as the atmospheric sensor so in a way the atmo sensor does not shut off if a gear is selected. I could see the 02 shut off at WOT if that is the demand.

If I understand correctly you can just unplug that sensor and get tested like Hub said .. you get only FI warning light but bike should work now without o2 sensor

No offense we have 2 things confused. We are not chasing the atmo plug is the same as the 02 sensor. Nor do we want to unplug this.

i do not known is map same than 1-3 gears in this way but should work.

Again, there is just one wire we want to mess with and that is the GPS wire. We default to the top gears this way, have the flies open sooner. Ask I which one that does and that's the one you want. The GPS and subthrottle system are together so to trick it to the backup ignition map, this is one way.

... probably due to the the difference effect of IAP map than 55-75mph.

If you look at it as rpm vs. vacuum the mph does not enter into the picture. Maps are swapping all over vs. input demands. So it winds up being linear and your ass can't tell what map kicked in being that linear.

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o2 sensor is aka lambda sensor .. http://en.wikipedia.org/wiki/Oxygen_sensor

Thats what i meant , disconnect that sensor. european model closed loop area is 4-6th gears 0-60% tps and 0-6000rpm.

If bike works now 1-3 gears and o2 "unplugged" all gears .. o2 sensor could be defective.

o2 sensor could be defective.

Show me a defective 02 without code.

Our western bikes are preset at lambda too but in open loop. If I can make a part to set a binary number, I can set another sensor to mimic the same binary number. There is no getting away from the handcuffing called the, "Penultimate" preset.

No gear is going to move me out of lambda. See it yet? The steps called your defective 02 call as not defective. Your gears do not call the lambda. Following how I can theory up your theory and do you see it, page 3-44?

* Last updated by: Hub on 9/27/2014 @ 5:52 PM *

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Anyway, still got this flat spot between 3-4k and it's starting to drive me nuts. Anyone had anything similar and found how to cure this?
Cheers

"So, just on the gear thing...if I sit at 30mph in top, it's only showing about 1.5 - 2k...I can wind it open from there and go right through the 3-4k spot with no hesitation at all" ..... probably due to the the difference effect of IAP map than 55-75mph.

I will be happy to take a shot at this. Just fixed two of them here local, of them all describing the same thing. My 2007 also had the hole you describe. These bikes had No 02 sensor. So with that being said if your electrics are sorted and problems persists and you can't get anyone local to fix use me as your last resort. Shoot me a PM

Daryl here on the Forum is suffering from the same problem on the 14 he gave to his son. I have yet to see his sons bike but I'm sure I goyt this. Results are all that matters not my opinion, if I can help I will. Cheers

Rick

If I recall, I think a euro might have one of those french ticklers in the velocity stack and those should be updated to a western rubber baby bumper of a v-stack.

Might that be the sneeze problem @ 3-4k?

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Only your service cap knows for sure. (under tank and pick which door), for 200 dollars, Alex.

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"No gear is going to move me out of lambda"

thats maybe western bikes but european model are not same , they works like i said. (08-11 models)

If i look my bike dynoded PCV map , 1-3 gears are +/- numbers 100% of tps area. but 4-6 gears those areas which I have already said 0-60%tps and 0-6000rpm are marked all +8 .. dyno guy said that o2 sensor(+optimizer if bike have it) override that area anyway and there is no point in trying to adjust.

One other thing has been noticed that some of 08 bikes works with o2 eliminator , but some dont and need optimizer like 09. Although any changes are not told by Kawasaki .. later models need for a signal change and a simple resistor do not work.

"Show me a defective 02 without code"

I've heard of at least one similar case that bike had some kind of power problem and not given a code.
Perhaps because of sensor is not completely broken but give false values or so and got bike totally lean.

Btw. I have removed my bike flies .. otherwise my mod "2nd gear on display" have no use.
I think it was a very noticeable change when bike have right map .. even bike is -09 and opening has been changed compared to the previous 06-07 models.

There are 2 fuel systems.

Open Loop = Western
Closed Loop = Euro.

Open Loop = Tunable.
Closed Loop = Not tunable.
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In the ECU, there is a way to run open and closed loops by flipping a switch.
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PAIR shuts off under pressure and then comes on when the rpm is lower.
The 02 can be used as PAIR or mimic this on/off and the optimizer is out of the loop as the dyno operator stated.
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Does the euro model have PAIR or a hose from under the frame down to the top front valve covers are those hoses, yes or no? See where I'm trying to agree some but if that PAIR is there... Hello?

And yes, the most obvious is a jobber out of spec and no code present. Same as having a spark plug fire but breaks up at higher rpm, whereas a new set of plugs would not cause the old worn out plugs to cause this... is one example of no code present. Same as no spark but it comes back as in a faulty crank sensor and that being heat related.

One more time. I rev in N I still receive the same input signal as goes out the output. No gear changes my lambda if the engine revs on its own or in gear it is vacuum demand if if not there then 760mmHg is basic FI.
One more time chewed twice. When you had a points bike/vacuum advanced cars/HEI ign/ show me the transmission having anything to do with the rpm range of the throttle demand and that jet sent in said demand no FI or trans needed, yes or no?

WOT is still present as a demand signal? Vacuum hose off the rubber diaphragm and now a vacuum hose off an intake sensor but now electronically moved times crank speed and vacuum measured = Fuel Entry.

AFR METER on an 02 (aprilia) = A constant 14.7 lambda pounding out that number on the 02 it came with = Closed Loop.

AFR METER on an open 14 = I can put that pc number on any AFR scale and add an excel number and it sits there in that map setting until I flip the pc switch to the other map in all zero it goes to the preset of 14-AFR and change.

Show me you AFR meter off the bike in each gear or do you want to watch mine?

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Does the euro have a GPS at the transmission? It does? There is no vacuum advance curve we find springs on that crank's tone wheel? No we don't. So how is it a curve is still needed? We do it via the vacuum w/gps? Yes.

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Oh you have the evolution going on here. Ivan had the hot hack to the GPS. What did that do? It altered the ignition curve from zip to zop. No hack, you had a linear curve all smooth. But with the GPS getting a whack signal out of range, the light comes on fandago, the backup kicks in and here is your 5-6 map stuck in code saying we set the ignition curve from 10° to the preset limped ignition curve be it more peppy on your ass but the dyno said you lost HP so says the book... 'We take measures...'

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There is another forum posts , failed o2 sensors and closed loop areas etc.

If the 02 sensor is playing up you may not get any error codes.... but you will if you unplug it..

My 02 sensor failed, the symptoms were mainly seen as :

When slowing down in say 4th or 5th gear with closed throttle, opening the throttle slowy again to pick up speed, the bike would just die like it was running out of fuel, until I got past about half throttle, then it would pick up again.

I tested my sensor with a voltmeter and blowtorch... I could see that instead of a nice clean switch from rich/lean it would take a long time to switch, in effect what was happening was that the sensor was telling the ECU that the AFR was too rich, thus leaning out the fuel injection, of course as soon as you get out of the closed loop area, >60% throttle, >6000rpm then it would suddenly take off again as it switched to the regular fixed map.

It took me a while to figure this out.

I picked up a new sensor off ebay from a ZX6R for £25, fitted it and it worked fine....just to be sure I switched back to the old one and it faulted again.

The only way to check the sensor is with a voltmeter and blowtorch, it should switch between approx 0v and 1v as you remove the oxygen by heating it with the flame, mine switched from 0v to 1v, then stayed there for about 30secs even with the flame removed, the new one switched immediately. This is a classic failure mode of 02 sensors, if you google it there's loads of info.

Good luck

Yes you can run it without any problem at all. Operation in 1st 2nd & 3rd gears does not use the 02 sensor anyway, the closed loop area is only very small, 4th 5th & 6th gears only, less than 60% throttle and less than 6000rpm.

Without the sensor the map in the ECU just has fixed values for the closed loop area injector durations, just the same way as it does for the open loop area (think of the fuel map as a large 3D spreadsheet for each gear with the two main axis being throttle position & RPM) When you enter the closed loop area, the map values are just overwritten by the 02 sensor signal, without the signal you'll just run the default ECU map, which is set for a "safe" slightly rich setting.

On the earlier ZZR's <2008 the 02 sensor could just be totaly unplugged and replaced with a resistor plug to stop the bike going into closed loop control & to switch off the error light on the dash, ie when using a power commander. On the new bikes 2009 onwards they got a bit clever with the system, and made the ECU look for a constant changing signal from the sensor. If you fit the resistor plug from the older models to the new bikes, you won't get the error message on the dash.... however the bike will not run in the closed loop area correctly as the ECU is totally confused, becasue it thinks the sensor is connected, but can't see the the 02 sensor signal changing. A lot of people got caught out with this when fitting power commanders to later bikes. Dynojet now make an 02 optimizer, which is needed to get the bike to run in the closed loop area with a power commander.

The 02 optimizer is used with the standard sensor, but it re-calibrates the signal so that it controls the AFR to 13.6:1 in the closed loop area instead of 14.7:1 this makes the bike run much better. In fact you can use the 02 optimizer without a power commander just to get better fueling. Dynojet know this a wont sell you an 02 optimizer without you giving them the serial number of your Power Commander

Ok, been doing some research. Most of this comes from Kawasaki and the guy who let Dynojet use his bike when they first developed their optimiser. A lot of this is a repeat but there are differences!

First off, the '06 - '07 models do not have the O2 sensor. It still has the air pressure sensor. It's ECU part no. is 211750090.

There is NO difference between the '08 bike and the '09 - '11 bikes as was previously thought on here.

The '08 - '11 bikes have the same ECU (part no. 270020007) plus both have an additional stack unit (part no. 211750154). They also have the same O2 sensor. Their ECUs monitor the lambda exactly the same way. The US versions do not have the O2 sensor fitted (ECU part no. 211750152).

The '08 - '11 model ECUs must have the varying resistance reading from the O2 sensor otherwise it goes into some strange mapping, jerks about and you get the annoying F1 error display. The ECU will always override any changes made by a PC (or Autotune etc) to a AFR of 14.7:1 within the closed loop area of <6k rpm or <60% throttle in the top three gears. Open loop AFR can be dictated by a PC/Autotune etc.

The only way to change the AFR inside the closed loop is by using an optimiser. The optimiser tricks the ECU into giving a set 13.6:1 AFR. No software can change this but the optimiser itself can be altered from within to alter the fixed AFR to a different setting.

For absolute maximum power, a AFR of 12.8:1 or thereabouts is best but the only way you're going to get that is by physically changing the optimiser internals. MPG will suffer, obviously.

So, to sum up, in closed loop, the ECU gives a fixed air to fuel ratio of 14.7:1. A PC/Autotune will change your bike's mapping everywhere except in the closed loop area. In this area, the bike's ECU has the last say over any other device to give a 14.7:1 AFR. The only way to change this is to fit an optimiser which tricks the ECU into giving a fixed AFR setting of 13.6:1. The only way to change this is to change the optimiser from within.

Still researching but hope this at least clarifies the standing of the '08 models.

[q]Does the euro model have PAIR or a hose from under the frame down to the top front valve covers are those hoses, yes or no? See where I'm trying to agree some but if that PAIR is there... Hello?[q]

Signed,

NOL to the Truth Tables

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however the bike will not run in the closed loop area correctly as the ECU is totally confused, because it thinks the sensor is connected, but can't see the the 02 sensor signal changing.

This is all about signal changing and if the sensor fails the 'backup' takes over...'we prevent issues.'

The '08 - '11 model ECUs must have the varying resistance reading from the O2 sensor otherwise it goes into some strange mapping, jerks about and you get the annoying F1 error display.

WATT did I just explain about the vacuum being lost? WATT did I say about Ivan's little trick to the GPS and we have an abrupt ["JERKS"] ignition on/off, no longer in linear curve....'we take measures to prevent damage.'

Since 1999, nada has changed from the first busa to this latest model to the H2. You are handcuffed to the Penultimate number is who rules the backup maps. Sensors rule the linear maps.

Open loop fails = Backs up to the Penultimate number.
Closed loop fails = Backs up to the Penultimate number.

Tunable = Backup
Tunable = Open
Not tunable = Closed

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