My 2007 ZX14 bogs down and stutters from idle to about 5,000 RPM then it comes alive I have sprayed water on the header pipes and cylinder number three while idling the water does not evaporate for ages so with the choppy Idol and acceleration it tells me cylinder number three is dead.. what's weird is after 5,000 RPM it goes like a dog shot in the arse... it has a new filter in the fuel pump that's about all I've done so far any suggestions?

What's mileage? Are spark plugs fresh? With the age, I would suspect the stick coil is failing. Could possibly be the ECU. Probably not a wiring issue, although it's possible maybe you have some sort of bizarre short. People have had some weird shit happen when water got into just the right (wrong) places and had a pin hole short.

I would do a compression check on 3 just to ensure there's no mechanical issue. When engine failures occur, 3 seems to be fairly common point of failure (mostly bearing type issues.)

I have a hadheld rpm tester for stick coil motors. Since this picks up the frequency of the coil firing, it's possible it MIGHT detect an anomaly measuring one stick coil vs another. IE, at the lower RPMs it might not read anything if the coil isn't firing, but would on other cylinders.

I would start with swapping stick coils and see if the problem moves. While in there , change spark plugs if it's been over 7500 miles since they were changed. While you have it apart, compression test. I'm sure there's a diagnostic process for the stick coils - although since it's working intermittently it MIGHT read OK based on resistances or whatever, but still be the cause of the problem. I would say if you swap 3 and 4's coil, and 4 becomes dead until higher RPMs, sufficient diagnosis - replace stick coil.

Thanks for the reply, bike has done 15500kms, original plugs, it sat for 3 years until this time last year, fuck I hope it's something cheapish and easy ??????

It MIGHT just be the plugs. These plugs erode from firing, basically every time they fire a tiny bit of the plug is eroded. So it might just be that 3 has more plug wear and where the electrode is centered is causing the problem you're describing. Plugs are 7500mi/12k kms, so they aren't extremely over but most likely you would notice a difference in performance just from a fresh set of plugs.

I would still recommend the same process, and it WILL be a bit of work. Even changing the plugs on these things is a little painful just because of the space.If you were hiring this done, I could see a professional mechanic needing about 6-8 hours. Double that for DIYER that doesn't do this every day.

While you have it all apart, I would probably also change the coolant and do a throttle body sync, air filters not due for another 4k miles (~6k km) but you could inspect and blow it out. Also...oil/filter change if it's needed.

Ok I have noticed on the dashboard when the battery gets to around 13.5 volts it starts to play up.. it always used to sit at around 14.2 volts all the time and never had an issue so what that's be? The battery most of the time shows 14.2 thereabouts it's on a trickle charger so the battery is always topped up

I concur with Vic's suggestions. So the recap is:
1. The simple swap of spark sticks to see of cyl4 stays cold/warm at the header within seconds and turn off. So that's with a cold engine.

2. Cyl3 remains cold on the swap, it's a full replacement of all plugs. Must use iridium and do not cheap out for others. I'm sure Vic felt the same E-ticket ride and signs off after a few hundred miles or more. Kind of feels digital at the seat of the pants.

3. Just the stick swap will show if the mechanical needs to be checked. Trick to a spark stick removal is a twist first and then up and twist as you go.

I'd replace the battery with the factory issue. Sure, you can use another brand, but I can get 9yrs out of an OEM if 'prepped' the way I wet a battery. Wet/charge/install gets you 5yrs on one. Prep is wet/wait/fully charge/drain down to 2v and recharge fully. Drain 2 more cycles like that, and 3rd fully charge is now installed for service.

A smart charger seems to bring it to a full charge. Say if I use a single rated charger, meaning: I need the rated amp for said battery. This means using at least a 1.2amp rated charger for a 12N12a battery. For the 14, I would need at least a 1.4amp charger for a 12N14a battery.

The formula is moving a decimal point over to the right for the amperage of the charger, and charge the battery for literally 14hrs @ 1,4amp. Formula for the 12N12a is to find a 1.2amp rated set charger and charge for 12hrs. Figured if Jay Leno uses a Ctek smart charger for all his bikes and cars, I'd set charge the battery with the 1.5a charger I have, pull it off an hour less say for the over amp, then let the Ctek finish it off.

Sort of noticed it took awhile to have all the lights lit for the Ctek. Still without it back in the mid teens of 2000, I could get 9yrs on the set charger when recharging from 2v.

With that said, the dash numbers are like a volt meter. Meter either blanks out, burns out that tiny screen so nothing shows, guessing, so figure it's not the dash. Figure the battery is degrading. Age and prep rears its ugly head.

Volts means PUSH. Think of pushing the starter motor over. No PUSH in reserve is all about storing volts. I'm going to use real world numbers where you never take your eyes off a remote voltmeter like a cheap digital from harbor freight. This viewing will point out the 3 components of the charging system and who of the 3 is the problem child.

1. 12.8v or more: This is fresh off the battery charger and sat for a few hours off the charger.

2. 12.8v key on: This should show a steady 12.8v

3. 11.1v load: This is more like a bench test of the starter motor, i.e., a battery load test using the bike.

4. 12.8v recovery: That is why you don't take your eyes off the meter due to it started up the bike.

5. 14.4v reading: The bike shows a perfect loop of the charging system. Instant charging at idle.

Points out numbers of the 3 components that expose themselves via volt readings:

Battery:
Bad - Under the 12.8v recover window shows lower.

Voltage Regulator:
Bad - Spikes over 14.9v shows a VR that can't convert the higher voltage output of the stator to a steady 14.4v.

Stator:
Bad - Recovery number 12.8v remains steady while idling. The term 'total loss' ignition system comes to mind. Just enough for a few laps and then dies.

mine had a miss at idle it was spark plug

Yep, 99% of the time I'd say that's true.

I had the #4 coil fail. You have good suggestions from the others. The only thing ill add is that I don't think changing is that hard. Used the tool kit socket and it took me about an hour and a half

Mad

I appreciate all the replies I ordered a new air filter and new plugs today I changed the fuel filter in the fuel pump last weekend which obviously didn't work I'll keep you updated most likely this weekend

I changed the plugs this afternoon now it rides like a brand new bike thanks to everyone for their suggestions

Glad to hear it was just plugs. I'm not surprised it was just plugs, even with the bike's age. My first response was based on the bike being up on maintenance.

I was shocked when I let my plugs go over a couple thousand miles and changed them.

Obviously you've now experienced the same thing.

Great news!

When I owned my 89 ZX10 Ninja I lost s spark plug sitting over 1 winter. It only had 16,000 miles. Fresh plugs and back to normal.
That was an easy Bike to do valve clearance with "shims" on top of the buckets.