I have an 06 ZX-14, flies out, Muzzy slip-ons and a PC III. My bike has done 66,000 km, but it is in great condition. It has been regularly serviced by a competent mechanic and has been reliable over 7 years of ownership.

A month ago, I went for a ride. I filled up before going out, and the bike initially ran smoothly. It then suddenly started playing up. It runs fine up to 3,000-3,500 rpm, but above that, it is very jerky and cuts out repeatedly. I suspected dirty fuel, because we had had a massive amount of rain the previous week and lots of bikers had issues with fuel contaminated by water and dirt at the time.

I have already tried the following:
1. The plugs were changed at 60,000 km, so they should still be fine.
2. I drained the fuel tank and ran a tank with fuel injector cleaner through it. I was unable to ride it hard, because it would not rev much beyond 3,000 rpm.
3. I removed and opened the fuel pump, cleaned whatever dirt there was (not a lot, IMHO).
4. I replaced the fuel pump with a new one.
5. I reloaded the fuel map.
6. I cleaned the PC III ground connector and the connection point behind the water bottle with sandpaper.
7. I disconnected the PC III and tried running it without it.
None of these steps solved the problem. It still runs fine up to 3,000 rpm, but above that, it revs-cuts out-revs-cuts out. This happens in any gear, including neutral.

What else can it be? Fuel injectors? If they are blocked, would the bike behave normally below 3,000 rpm?

1. Air cleaner dirty?
2. Cuts out would show more of a code from any of the telemetry like spark coil/IPA/injector failure.
3. This is where you take a long spark plug lead, use a timing light so this is clamped over the plug wire and see if the ignition cuts out, since you changed to a new fuel pump. What this says is a possible bad ECU.

And the only way to find this out is install any ECU within the years 2006 to 2011. Though the injectors are not a match with some years, it's the checking of running over 3k is to plug in their ECU to see if this cleans up the drop in rpm; if it's not a clogged/dirty air cleaner.

I will check the air filter. My mechanic says he ran a diagnostics test, and it did not throw any error codes. Will try to source another ECU.

'My mechanic ran a diagnostics test and it did not have any saved error codes.'... is how I'm reading this. You can ring yours up and check with the mode button(s). So he would have to have the diagnostic tool to see if any saved codes are present and that means a phantom code has popped up but cleared itself within seconds.

I pop codes all the time and this baby is slow in the processing to clear them. I'm talking a few seconds, if not literally a good full second of wait time. The only other thing I can think of is crank sensor? If you say cold or hot either way she starts, then not heat related is one. So if we think cold is a range check, we pull it again and check for a hot range and is it out of range hot?

So this first check is to see if the bike revs without the air cleaner? Say the a/c looks questionable, so instead of buying new, a quick whack of the throttle over 3,000 rpm is to see what happens?

Set the meter to x100 ohms range, unplug the right side crank sensor connector. It is one long wire, wrapped around a core, and out the other end it goes is that single wire. So it says, checking for a break in one wire; does not matter where you swap prongs to whom, it reads the same. So that said, it has a resistance number of between 376-564 ohms. It falls in between there no matter hot or cold check, it's not the crank sensor.

I'll sleep on it. It's got me stumped.

It's not the air cleaner - bike does the same thing with the air cleaner removed.
Also not the crank position sensor - measured it and it's within specs at 434 Ohms.
Bike starts normally, whether it is hot or cold.

* Last updated by: jcsquare on 6/15/2015 @ 4:31 AM *

jc, without riding it to narrow down a driveability issue, I've let my intake vac sensor become disabled, threw a code and I could not accelerate up around that range without a huge knock and bang under hard acceleration. Something like that will throw a code. And here is where I can't tell if both produce the same effect... not without a ride.

So the next try is to find a straight plug cap to reach down into the plug recess, run a long ign wire out of the cap and head, install a tiny screw into the end of the plug wire, where you ground a point at one end, sawed off the head; the threads run up the spark stick; being you found a screw size to fit into the spark stick.

This is where you then take a timing light, clamp the pickup wire over the long spark plug wire you made; start the bike; hold the timing light trigger down and rev the engine. If it cuts out at 3k; flickers the light and is not steady = ECU... you'd think.

And now we are back to the ECU, because I questioned the crank not being it. Why? Starts too fast, does not cut out hot, but only up to this rpm. Next test is narrow it down to the ECU?

What else can it be? Fuel injectors? If they are blocked, would the bike behave normally below 3,000 rpm?

If all are warm, not idle popping, meaning, not popping at the quick test, nor when riding/idling hot; then you'd assume no clogged injector holes.

The 3 basic variables are fuel/spark/compression.

Compression: Figure it runs, idles smooth, etc., is the given.
Spark: It sparks but here are the same sort of symptoms between this and fuel.
Fuel: You know the gas is fresh, new pump, idles fine, and now you wonder if this is spark related is that timing light will tell it's not fuel she 'goes on the blink@3k.'

Thanks, Hub. I'm going to try this tomorrow. Middle of the night ATM, and the neighbours won't appreciate even a 1 second test.

I checked the headers after running the engine for a short time. The pipes are equally warm. The bike also idles evenly. I don't think the bike is running on only 3 cylinders, at least not at low revs.

I ordered an 07 ECU off eBay. It will take some time to get here all the way from Virginia. I will therefore not be riding for at least another 2 weeks. The low-mileage, 07 CBR1100XX that I have been eyeing is becoming more tempting with each passing day ...

jc, that may have not been an ideal ECU of choice. Go look under the header, right side, just forward of the collector where all the pipes funnel into. Do you see an 02 sensor hanging out of the header? So what you bought was an open loop ECU for a closed looped bike. That, or if you matched your ECU part number off the black box, found one on ebay... I think you'll be fine. If on the other hand this is not a compatible ECU, it still will show if this cleaned up the glitch. No codes popped when installed? Go for it!

I will check to see whether my bike has an O2 sensor. However, I have learned that the ECU that I bought is indeed not a perfect match for mine. I bought part number 21175-0084 (US model). I checked and the European model's ECU is 21175-0102, and it seems that Australia (mine) has yet another: 21175-0090. Anyway, the new part is almost $1,200 here, and I cannot find any used ones for sale locally. I hope the American one works, or else I have just bought an expensive paperweight.

Hub, I checked and my bike does not have an O2 lambda sensor on the exhaust.
Just to clarify - I won't need new keys with a new ECU, right? Do I just follow the steps described in the service manual of pairing my existing master key and user keys with the new ECU?

I think I read it has to meet a certain ping for it to light up. Something like 4 settings. So it might need a ping from the dealer and his kawi-kit or whatever the key security communication download is needed. That, or it lights right off no problem. So you figure it won't start is the ping is in need of a resetting.

Last night and this morning, I started the bike and revved it without warming it up first. Revs all the way to the red line! However, when I tried it earlier today after letting it warm up, it stuttered at 3,000 rpm. What does that tell you?

jcsquare, why don't you take it to the mechanic that's been working on it the bike's entire life? Especially considering you bought a AUS$1200 ECU for the bike which you might not even be able to use? US ECUs do not have the immobilizer feature European and Australian models do.

Vic, where is that short stock blip vs flash? Lost it didn't you?

jc, dealer level has the diagnostic kit if not, s'he needs to read their contract is to have said equipment on hand etc. So they go in there and one radio click, she starts as if, hello?

This is where it takes years for the computer bike to come with that glitch and know where to look? I'm just guessing and they go nowhere. Here's watt I wouldn't have done. Buy the ECU. In other words, it would ride up to 3k, so off to a dealer or used bike shop, or bike for sale kind of swap the ECU rather than buy half a brick? That's; lost new brick money that could have gone to... IF... finding one to swap and it WAS the ECU, half that money is burned towards a used one that may not work with the key ping. Then, new key switch assembly for a non-alarm 14.

Now, you threw parts at it, and this was more what I meant was.. WE do not know where to look? There are no codes that pop up and explain where the signal is not being [watt I think is a filtering] or a poor square wave is in a saw blade kind of pattern ['signal our of range'].

If I had a scope that could hookup to every sensor, had all the squares saved is a good known running bike. I find where the one sawtooth wave pops up on the sensor in question... See how you could scope a square to a sawtooth pattern?

WARMUP:

WATT can I determine from this?
1. Heat is the first clue. Why? 2 things are happening.
a. The bike is set to morning map; where the actuator opens the throttle plate via the ramp connection.
b. The ramp is closed when warm, but since I can't ride the bike, run my timing light test for fuel or spark, I have to come up with why it revs cold, stumbles hot?
c. So morning map system is; the ramp closes or you'd rev without touching the throttle it idles high.
d. That says it closes the morning rich too you'd assume; if the ramp works, so will the change in map?

2. Heat in the cold engine is to fatten up the fuel to air so when hot, atomization is in play with the help of expansion of the heat happening. So I can't say the morning map is on or say too rich and it stalls warmed in other words.
a. No stall and idles as if nothing is wrong, correct?
b. Starts right up warm is no morning map or rich condition is occurring. Correct?
c. Heat begins to happen to most of the sensors in all sorts of temps. Signal out of range? No for now.
d. The crank sensor is a lot hotter than say the tps that is not hooked to the engine's heat. Still runs.

3. Heat, when up to running temp, is the second part happening; is heat to the telemetry.
a. Who has warmed up to temp, be it thru the water temp off the back of the engine, the crank sensor splashed with oil heat, the 5v sent to the other sensors is heat travels thru a wire and who is breaking down when heat rises = Resistance Occurs becomes the ^^^^^^ hacksaw wave, not the |_________|square wave.
b. I'm going to assume that is how the computer is sending out the output is junk in.
c. This move is going to cost you more in home schooling, meaning, self-diagnosing tuition money.
d. You now bring in a variable of cold rev/warm stumble is I'm sure is heat related.

4th Variable(s):
a. Cold = Every sensor is within spec, yes or no?
b. Hot = Here comes the 3k Glitch.
c. Can't be the crank is possible cold or hot it might send in junk. No, can't be a sensor is if it's out of spec cold, it's out of spec hot no code present. So, the ECU is not programmed like the ape where it shows you what winker side bulb is out front or rear.
d. Water temp sensor? That more stumbles right out the gate.
e. That one tube off the intake vac would code. The wire off the vac would code. The bike would stall with the air leak; the wire off would mimic the harsh stumble is an intake sensor.
f. Which brings me back to the ECU not swapping [out of] map when warm?
g. Which brings to a disconnect I pull this out of my rectal cranium.

Lets move the 02 sensor? You don't have one? You have under the seat an atmospheric/intake sensor? What happens if we swap the intake with the atmo sensor? WATT happens if we remove the 02 connector and ride in code is the backup mapping/overrides current map.

So we have 3 tries?
1. If this has one... and I say this for the generic someone searches for a glitch with an 02, lets remove it and ride it warm to stumble. It it stumbles warm, it's not the 02 and backup.
2. If we take a golf tee and close the hose off the intake air sensor, warm rev, we still have the intake wired in.
3. We now remove the intake air vac and hook it back up to the sensor, now disconnect the sensor and rev warm.
4. Finally, if we have the atmo sensor sitting under the seat, left side rail, we want to swap those two, being they are the same sensor. So if it does not work, we just reconnect the atmo back onto the rail, we did not remove the IAP sensor, we just removed hose-check, we removed connector-check, we then installed the atmo into the IAP harness w/hose and let the atmo code who cares. This tells us if the IAP was the culprit.

Beats me?

LOL Hub I'm working on it. Been very busy with unfortunately more important issues. I did post a little bit in another thread I saw you were asking about this.

I want to be careful with this because I know what popular opinion is and I also know that not done right it's very easy to dismiss.

Vic, it takes no talent to pop the throttle open and see if that flash took it away. You still came away clueless. Only air pushing you is when you fart out the ass. But then again, I have no clue at what orifice it's coming from... hint... Shit Science is spewing out which orifice!??

By the time you read this and figure out if you should laugh or take offense to it, I'd be back by now and know either way gimme that shit you're busy. You're sitting on your ass answering is time wasted you go sitting on a bike and determine no diff between a flash and the OE.

Vic,

I did take it to the mechanic. He thought it was the fuel pump. I replaced it, and it did not solve the problem. He now reckons that the injectors need to be cleaned, but the fact that the engine runs fine up to 3k rpm, raises doubts in my mind. Being able to perform normally on a cold start brings even more questions. I am asking for help to find out whether owners who know this bike inside and out can come up with a more plausible cause for the problems. I am desperate to get it fixed.

The ECU was 2nd hand off eBay at a price much lower than a new one, and it appears that the non-Calfornia US spec bikes are in fact equipped with immobilisers.

I did take it to the mechanic. He thought it was the fuel pump. I replaced it, and it did not solve the problem. He now reckons that the injectors need to be cleaned, but the fact that the engine runs fine up to 3k rpm, raises doubts in my mind. Being able to perform normally on a cold start brings even more questions. I am asking for help to find out whether owners who know this bike inside and out can come up with a more plausible cause for the problems. I am desperate to get it fixed.

The ECU was 2nd hand off eBay at a price much lower than a new one, and it appears that the non-Calfornia US spec bikes are in fact equipped with immobilisers.

Refer to FUEL SYSTEM (DFI) 3-91 in your model's service manual.

ECU Identification
Part Number [A]
Specification
21175-0076 Europe, WVTA, Full, H, with Immobilizer
U.K., WVTA, Full, H, with Immobilizer
21175-0084 U.S.A (except California), without Immobilizer
Canada, without Immobilizer
21175-0089 U.S.A (California), without Immobilizer
21175-0101 Malaysia, with Immobilizer
21175-0090 Australia, with Immobilizer
21175-0102 France, WVTA, 78.2, H, with Immobilizer

Not sure what the effect is of using an ECU without immobilizer is on a bike that was originally equipped. If other components are supposed to talk to immobilizer I doubt it would work. If all someone has to do to defeat immobilizer is replace the ECU that's kind of scary to me. I hope it does work and fixes the issues, best of luck in that regard.

Vic, it takes no talent to pop the throttle open and see if that flash took it away. You still came away clueless. Only air pushing you is when you fart out the ass. But then again, I have no clue at what orifice it's coming from... hint... Shit Science is spewing out which orifice!??

By the time you read this and figure out if you should laugh or take offense to it, I'd be back by now and know either way gimme that shit you're busy. You're sitting on your ass answering is time wasted you go sitting on a bike and determine no diff between a flash and the OE.

Agreed, and again it's not so much the actual testing as logistics. We're coming up to more stable weather period now. That should help with conducting the testing. It's gonna happen... and I'm not sure who's side of the fence I'm going to be pissing on quite honestly.