Hello other zx14r enthusiasts, I am currently fighting a very annoying issue and need some help. About 30min to an hour into a ride my zx will cut power violently if asked to give more than about 50% load. It will then buck as though someone is closing the throttle and opening it rapidly. I have had it looked at by kawasaki techs, reputable tuners, and it has been on a dyno for diag. I cannot get it to duplicate the concern for any of these techs because I can't really ask them "hey go ride my bike hard for an hour and see if it try's to throw you over the bars" Does anyone have experience with a similar issue with there zx14r. INFO: bike has 60,000 miles, a tuned pcm, and full exhaust. To anyone that can help, Thank you.

Just a guess but fuel filter comes to mind, altho a shop should have checked that ??

I agree with Chrly - but also suspect clogged or failed injectors as well as the fuel filter in the pump.

On of our sage subject matter experts would probably say to check the header temp with an IR thermometer right after this is happening. If they are all hot and about the same temp then that suggests equal fuel flow into the cylinder via the injectors. If one or more is cooler than others that could be a clue.

Injectors can become intermittent but its not common

Thank you for the replies. The fuel filter has been looked into but an intermittent clog in the rail is not out of the question. It also tracks with the Is fact that once I cycle the key off and then back on it runs correctly for the first pull or two. I was also curious if there might be a issue with the throttle position sensor, is that a known issue?

So the filter in the pump has been replaced or a new pump/filter installed?

I dont recall if the TP sensor is an issue or not, I dont recall threads where that was or was not an issue - but I dont think it is but IDK

Is there an aftermarket Power Commander with a sketchy map installed? If there is a Power Commander installed try taking it out of the control loop entirely and see what happens

If you borrow or swap a known good stock (non-flashed) ECU that would eliminate a lot.

So you recently went on a long road trip in all kinds of weather, did you check all of the fuel related signal wires for shorts/opens? Corrosion on signal leads or grounds could cause intermittent gremlins. A Member in TX, Kruz just had a similar problem and it was a cut wire - maybe under the seat???

Hopefully HUB will add some color commentary and guru knowledge - we can help you try and decode if he does. I think he's from the Ukraine or some other socialist state like the west coast and his technical English is challenged ... but invaluable

ROOK is the other SME you could ping, I think he knows the TP sensor details too.

* Last updated by: cruderudy on 1/2/2022 @ 10:20 AM *

I still bet on the fuel filter unless changed.. It is restricting the flow of fuel so that it simply cannot keep up with prolonged supply at when throttle is more than 50% (?) opened, bike begins to run lean and shuts down.

* Last updated by: chrly on 1/2/2022 @ 2:04 PM *

Hopefully HUB will add some color commentary and guru knowledge - we can help you try and decode if he does. I think he's from the Ukraine or some other socialist state like the west coast and his technical English is challenged ... but invaluable

Yes, I am from Checkhislingosealaugheeha, and this google translation machine is being taxed I get a hold of it... anyway, sure sounds like E with the key cycling.

Funny, but over at the yammie sites, they have an adjustable TPS you need to keep an eye on. Plus, saved codes that still are in play until you clear the codes. Interesting.

But here, these are preset and do not even recommend moving them for any reason. Ask me how I know they will code within the slightest move. Not only that, it will be out of sync with the subthrottle, being they are both synced at the same open/close positions.

Bucking like that sure feels intake/TPS bronco kind of... I felt the same thing hack wise, if I catch how you describe it. So it's more back to a thermo window? The few minute warm up, then hammer the bike till this time frame comes in; and now at punishing heat thrown at it with the sportier ride that was from the start beings to happen, right?

So right off the bat I'd check for the chemical buildup at the (-) battery post. That means pull the tray and physically look if the shops did not. Then, you'd be checking the bolts being tight and if there is crust, you dip the cable in vinegar, wipe the crust off the battery with tap water and q-tip. Nut and bolt in with the vinny. Then scrape the lead battery post clean with a single edge razor, scrape clean the cable end so both have fresh contact points.

The next is to unclip the TPS and reclip a few times so this scratches new metal at the pins. If say you look at the connector pins and they are green looking, then this too is dipped in vinegar, clean with fresh water. Contact clean the TPS pins with a cotton q-tip to clean up that electrolysis.

No codes so no down sensors in the loop... just a high miler with maybe some flow hang up at the connector points? Fuel pump wise gets taxed a lot at the beginning, but does not occur till say this time window going in that seems like it's more electrical with the key being cycled and cleared of some off signal due to heat?

Okay, were are my US interpreters for this post sent?

* Last updated by: Hub on 1/2/2022 @ 3:41 PM *

I haf this happen one time on my 2008. It was right after a wash with garden hose. My guess is the speed sensor couplings got water in them. I have a Speedohealer on the bike and the couplings are not the greatest. The speedometer went crazy during the bucking too and finally the speedo just went to 0 and the bike ran fine. A few hours later, the speedo and bike worked fine. I taped up the speed sensor couplings and never washed with a hose again. Never had the problem come back. Your Gen2 has a different speed sensor than my 08, I think but you might have a look at it.

Thanks for all the input guys. In order to diag the problem I have taken the bike to my tuner and run it on the dyno
a lot trying to duplicate the circumstances. The sniffer was reading good AF's the whole time. We couldn't get it to act like doeson the road but tune looks good. Yesterday I checked the battery terminals and ground and they are clean. I will be getting into the tps (both primary and secondary) next weekend.

Looking and adjusting a non-coded jobber is not something to look at. Without code, it says it's connected, no wire out of connector, no short, no signal out of range. That's how to read a bad sensor. No code, no point looking.., works without one of those variables in the mix.

Do not tamper with in other words... it is not the telemetry without it setting a code.

* Last updated by: Hub on 1/3/2022 @ 11:16 PM *