Dead Ninja

high 80's is pretty good for town riding with a bit of stop start

if you was on country roads I would expect it to be low 80's

if stop start traffic I would expect it to be around 100 - 110 and the fans cutting in and out

personally if it will run I would start the bike with the temp display showing and leave it to run until it reaches around 110°c if the fans haven't cut in by then then that needs to be looked at

I would say about 5 - 10 mins running to get to that temp

once the fans cut in or if they cut in then you should see a drop in temperature and it will just repeat the process

as long as the temp is going up and coming back down then you have a working cooling system

if the temp keeps climbing then you have a problem

electrical issues dont normally cause a carbed bike to misbehave with the revs!

carbed bikes misbehaving is usually air leaks or badly set up carbs blocked jets and sticking needles!

if they suffer electrical problems that affects the revs its normally the coils and the bike will drop a cylinder or two!

are the revs noticeably going up and down? I have seen electrical problems cause the rev counter to be higher but the actual revs stay the same

If you could have had these issues a month or two again I would have lived 10 miles away and sorted it.

Revs hopping around suggests fuelling at first, but with warning lights and it cutting out as well as running hot without fans kicking in suggests an electrical problem as the engine isn't being effectively managed. This can be caused by a number of things.

If coolant and oil levels are fine with no obvious leaks anywhere you shorten the list down to electrical.

Electrically the revs could be bothered by the ECU, especially if the bike has an auto-choke. The warning lights all coming on point at an ECU problem as it's unlikely you'd get the whole lot on at once. If the brain of the bike starts to get a bit senile, it all goes pear shaped fast.

But that's just a theory, it could be a cooling system that is having a knock on effect. First check the electrical connections on the bike, connectors, wire condition and even just being really simple; unplug the ECU, spray some contact cleaner in there and let it dry before putting it back in. And see what happens. I've seen bikes go bonkers over a loose connection.

if it was fuel injected fozzie some of this could be true but is carbed

no engine management goes on with the ECU

if it was fuel injected fozzie some of this could be true but is carbed

no engine management goes on with the ECU

I've seen a few carbed bikes with an auto-choke. Really simple thing tied to the coolant/oil temperature so just wondered as the old GSXR had FI with a manual carb, and Hondas CBR got FI but kept the really simple autochoke, which was more hassle than it was worth. I've never had a run in with a ZX6R so just running through ideas.

The bike has pre-existing fueling problems we know of so could be that and something else has gone wrong too which is confusing the diagnosis.

If just the oil temp light I'd have all my money on the cooling, but the other lights suggest something else going on so I'm a little torn with what it is

manual choke on the zx6

If you were a bit closer I could have at least done a quick relative compression test for you, take all of 2 mins to set the scope up for it. I do have a proper tester to confirm issues.

no engine management goes on with the ECU

Surely the ignition timing is controlled?

 

no engine management goes on with the ECU

Surely the ignition timing is controlled?

Not really

You have a pick up to tell the ecu to fire the plugs and that's about it!

If this was causing trouble the revs wouldn't act like they are and the bike would struggle to run so that's ruled out straight away

It should have different maps for temperature, gear selection and maybe throttle position too if it has a sensor. So it will be "managed" to a degree.

So many basic things to check first though that require a degree of confidence and knowledge to say "that's o.k." and not rule anything out and miss the problem. We could speculate the potential issues all day, it needs to be looked at.

Weather is looking ok tomorrow so I should be able to have a tinker.

Going to run it first to ensure the fans are kicking on and cooling it down, check fan connections, thermostat, water pump etc

Hopefully borrowing a voltmeter to check battery is ok, fuses, check wiring is all looking ok

Time permitting I need to change the oil anyway and will look at replacing coolant (which I think is fine but...)

I am keeping everything crossed that it is something simple that can be easily fixed and then we can go back to discussing the backfire issue

It should have different maps for temperature, gear selection and maybe throttle position too if it has a sensor. So it will be "managed" to a degree.

So many basic things to check first though that require a degree of confidence and knowledge to say "that's o.k." and not rule anything out and miss the problem. We could speculate the potential issues all day, it needs to be looked at.

Not on a carbed bike it won't!

Only on fuel injection!

They ecu has no control over the carbs

Are you sure? The ecu must at least advance the ignition or retard it depending on the values from those sensors? I can't see how the advance system would function with a single ignition map, without having a vacuum advance or a mechanical system.

I didn't mention carbs or injection, just the ignition side of things.

If it's a manual choke on a carbed bike the ECU only really governs spark timing. So unless it was causing it to advance suddenly (which can increase cylinder temperature and might explain why it was so hot) then it has to be partly a fuelling issue as well.

It's an issue on the engines here at work can suffer, if the ignition is advanced too much you risk melting spark plugs.

Unsure if it would cause the 500-700rpm leap even though it's a small jump really. But what I've suggested would be quite an oddball problem to occur so wouldn't take it too seriously.

Eliminate easy problems first.

If the tps (if it has one) is stuck just off the idle position and the bike throttle (cable) is in the idle position, the bike will definitely run badly.

So.. bike started fine today (no backfire) rode it the 2 mins to work area and ran it up to temp. Fans kick in at 103 and bring it quickly down to 98. Did this three times no issues.

Everything else seems fine... which is annoying as hell as I'm no close to knowing what happened

Think I'm going to have to take it to work Monday (will have other half behind in case anything happens) and keep an eye on the temp over a longer ride. Getting some redex tomorrow so will put that through

Update: Started fine today and behaved itself all the way to work.

Stopped for fuel and put the first round of redex through.

In traffic temp got up to 80, riding round it was between 67 - 74.

I'm guessing it's going to be fine for ages then just randomly do it again at some point Maybe an electrical issue if it's intermittent?

Probably, i'd take a good look at your connections in the wiring loom, as many as possible and clean them up. Things like your battery connections should be spotless enough to nearly see your face in them, dab a bit of vaseline on them if you haven't got any dielectric grease to stop them from furring up.

It doesn't take a lot (sometimes as little as a single volt loss) for 12v electrical system to play up.

This is crying electrical connector issue.

Check the loom, unplug things, spray contact cleaner and reconnect firmly. Also look for worn through cables as if something like your tail light shorted out on the frame it could cause more mayhem than you think!

Unplug the ECU and plug it back in after cleaning the connectors. Then keep an eye on it.

To make the revs rise or fall you open or close the throttle or the choke on a carbed bike, you have to add fuel and air to make it rev higher and as there is no electrical control over the fuelling then its impossible for an electrical issue to cause the revs to rise

if the ignition was been advanced or retarded when it shouldn't be then the bike would run rough or not at all

your cooling system sounds to be running just fine

I think you have a sticking float personally which is over filling a carb and leaking fuel in to one of the cylinders hence the higher revs the back firing can be caused by said float that's stuck leaking fuel in to the cylinder when the bike is turned off which can then also enter the exhaust where its been ignited and causing a back fire

I would also check all the throttle linkage and all cables to make sure they are all free

also a vacuum leak can cause higher idle

as for the cutting out its cold outside and it will be prone to carb icing this could be the reason for it to cut out my mate had the 99 model zx6 and some days on his trip to work in winter it would cut out 5 or 6 times because of carb icing! it was a right twat for it!

you don't have an ECU on your bike its called an ignitor unit or CDI ....an ecu and CDI are different! and ECU is a Engine Control Unit they read various sensors and control fuelling maps and auto choke and tell the injectors how much fuel and when to inject it....if you had an ECU it could have been electrical but seen as though yours is carbed you only have a CDI box which controls the ingition and that is all it basically tells the bike when to spark and can control ignition advance or retard

I wouldn't call it engine "management" it just tell it when it needs to light the fuel in the cylinders!

now if your bike runs sweet as a nut with no coughing and farting whilst riding then your ignition circuit (CDI box and sensors ) are all working fine!

if the bike is just revving high then you are getting either extra fuel or air in to the cylinders there is no other way a carbed bike can rev high without either of these

now are you sure that the revs are increasing? can you hear the revs increase or is it just on the tacho that you can see it?

if the tacho is just reading high but the revs aren't actually rising then you may have a bad earth on the wiring up front! as looking at the wiring diagram for your bike the earths all run in to one and the feed for the oil lamp is fed to the tacho and so a dodgy earth could have back feed power to your coolant light

you may have more than one problem here

http://attach.kawiforums.com/2006/07/17/20060717111254-1-7986.jpg

So advancing the ignition or retarding it (caused by an offset TPS) wouldn't have any effect on the idle speed on a carbed vehicle?

Why do you think you had to remove/plug the vacuum advance pipe on older carbed cars to set the base idle? Because it was typically 2-300rpm lower with it off and not functioning.

Edit to add, I may be wrong in this instance but try loosening the securing screw and twist the TPS a little on a carbed bike to see what it does to the idle speed. I am 99% sure that it will have an effect, too drastic a turn and yeah it probably will stall out.

Hi Stu

When the revs went up it was audible not just on the dial. Starting from cold on the choke it will merrily tick over at about 1600 then suddenly shoot up to over 4000. Turning the choke down will reduce back to normal then shoot up again so choke down again. After a minute or so it will happily settle It's fine when I'm riding as I wait until it settles down but took the other half by surprise when he rode a while back!

Stuck float is on my list to check bit not having indoor or lit work area it's a bit of a bugger to check in the wind and wet! Hoping the redex may help a bit.

I've been told I have many problems

So advancing the ignition or retarding it (caused by an offset TPS) wouldn't have any effect on the idle speed on a carbed vehicle?

Why do you think you had to remove/plug the vacuum advance pipe on older carbed cars to set the base idle? Because it was typically 2-300rpm lower with it off and not functioning.

Edit to add, I may be wrong in this instance but try loosening the securing screw and twist the TPS a little on a carbed bike to see what it does to the idle speed. I am 99% sure that it will have an effect, too drastic a turn and yeah it probably will stall out.

the throttle isnt electronic controlled its wrist controlled tps would be in a fuel injected bike

hoggs to check for an air leak round the intake side with the bike running spray a bit of wd40 round the inlet rubbers and see if revs increase if they do then its a rubber inlet that is causing some of the problem im with stu on this one in general regarding ecu/cdi

I've been told I have many problems

If it'd make you feel better, I can recap all the problems I've had with my BMW

Im being lazy and cba to read 4 pages of this :D

I had similar issue my bike was fine then would cut out, Start up and be ok for a few minutes and then cut out. After a day or so of no use it was fine.

Turns out i had water getting into my spark plugs due to bad seals around the top. When ever i washed it or it rained water got in and it caused havoc. So new seals fixed that Month later i got new spark plugs to which helped.

Hi from what I've read, it would seem to me to be a fuelling issue, normally with an electrical fault the engine would be misfiring- popping and banging as the engine would still be pulling fuel but no spark to burn it. With the engine rev's dying then picking up suggest fuel starvation. Note: if there is a fuelling issue your engine will heat up and run hot as the fuelling will be lean. Have you checked the burn colour of the plugs? This should give a clear indication of what's going on in there.

http://www.verrill.com/moto/sellingguid ... rchart.htm

Hope this helps

Hey Chris, I replaced the plugs a while back they had a very thin white covering (not crusty like in the bottom left picture in your link) which I think means it's running a bit rich? The plugs were all in good nick otherwise.

Glorian I am outraged you can't be bothered to read the very very exciting thread about all the crap my bike has been doing