My ST ZX-9R Bec has a problem for the last 3 months or so and i'm in need of some expert advice on how to solve this as i'm unable to use it
due to fear of breaking down 
I've been told it's possibly the battery or reg/rec. If/when it fires up and runs it's absolutely fine until i turn the engine off then
it's like Russian roulette whether it's going to start up again or not. Sometimes it will start and others it totally refuses :-/
Any advice would be greatly appreciated.
Thanks in advance.
Daz.
quote:
Originally posted by Cadburys Man
My ST ZX-9R Bec has a problem for the last 3 months or so and i'm in need of some expert advice on how to solve this as i'm unable to use it due to fear of breaking down
I've been told it's possibly the battery or reg/rec. If/when it fires up and runs it's absolutely fine until i turn the engine off then it's like Russian roulette whether it's going to start up again or not. Sometimes it will start and others it totally refuses :-/
Any advice would be greatly appreciated.
Thanks in advance.
Daz.
When you say it won't start, do you mean its sluggish to turn over on the starter, or turns over fine but won't actually fire up ?
Cadburys Man - 11/7/16 at 07:10 PMIt turns over fine but if i try for too long it does slow down?
Also if it DOES start it never cuts out, the problem is only if you turn it off then try to restart it :-/
[Edited on 11/7/16 by Cadburys Man]
Toprivetguns - 11/7/16 at 08:04 PMCheck the Kawasaki manual and test the rectifier and alternator. If neither are working correctly your battery won't be charging properly.
I had the same problems with my zx10r
(Rectifier problems that is - not sluggish 2nd starts)
[Edited on 11/7/16 by Toprivetguns]
Cadburys Man - 11/7/16 at 08:05 PMAm i right in thinking the reg/rec controls the spark as well as charging the battery?
Toprivetguns - 11/7/16 at 08:12 PMFrom my basic knowledge the spark is controlled by the ecu.
The rectifier changes voltage from the alternator from AC to DC - they are quite prone to failing, hence insufficently charging of your battery.
I would check your battery voltages as per the manual and make sure all is working well.
You mentioned a sluggish second start? Not sure what that could be, perhaps the starter motor relay playing up?
Wadders - 11/7/16 at 09:25 PMeasy enough to check the regulator/rectifier if you have a dc voltmeter (multimeter)
Check the battery voltage across the battery terminals + and - with the engine off you should get a reading of approx 12vdc
start the engine and rev it up, meter should rise to approx 14v if the voltage doesn't rise at all the alternator is shot, if the voltage rises much higher than 14v the regulator is shot. i once had a faulty one shoving upwards of 40v into the system, which inevitably fried the battery and lots of other stuff besides.
Its also possible to test the output of the generator itself, set the meter to AC and you should have approx 70v AC on each of the three phases from the generator ( 3 yellow wires)
However all that said I'm not convinced the charging side is your problem. sounds possibly like heat is affecting something and causing either a weak spark or fuelling issues when the engine is hot.
i.e the motor starts fine from cold, but is struggling to restart once hot.
Start by getting the motor hot, then whip out all 4 plugs and see if you are still getting a nice fat blue spark, if not stick a new set of plugs in and also check the ignition coils, (there might be a resistance test you can perform hot and cold to test them) or try to borrow a set you know are ok.
Once you are satisfied its sparking ok start looking at the fuel side
Check the carb bowls are still filling up when the engine is hot, could be a dodgy fuel pump or a tank breather blocked.
twybrow - 11/7/16 at 10:19 PMUnless you are describing a low battery, i cant see the reg rec having anything to do with this issue. As above simply creates a dc voltage to charge the battery. It should run just fine even with this disconnected.
I would be looking for a wiring fault, probably on your starter circuit. If it only does it when hot, perhaps a wire is overloaded and thr heat is causing too much resistance and hence the poor starting....
CosKev3 - 11/7/16 at 11:30 PMBetter description of what it's like when it won't start or a video of it will help people diagnose it
Cadburys Man - 11/7/16 at 11:46 PMTbh it doesn't only do it when it's hot, it does it from cold as well, it's very intermittent and the weird thing is if it's running it will stay running until sometimes when i turn it off it will either start straight away or not at all :-/
Hope i'm making sense lol.
Daz.
CosKev3 - 12/7/16 at 06:55 AMStart with the basics,check your charging system is working and the battery is holding charge,get it drop tested too.
Then check,removing if necessary,all the main power cables to the start relay,and the earths off the battery.
Get yourself a aerosol of electrical connection cleaner incase any connections/earth points are corroded, clean them up with emery cloth or the like.
What is your engine wiring like?is it all tidy and secure,or more like a birds nest like lots of kit cars?!?!
ReMan - 12/7/16 at 07:24 AMI peresume this is a sm small bike battery that you have on the car?
The reg can cause strange problems I I I I I think that it's to do with dirty DC upsetting the ECU even this is the charging still happens
As mentioned definitely check this it's easy enough as is checking for a spark as above
then look at fuel, try with some easy tart etc.....
Cadburys Man - 18/7/16 at 12:21 AMreg/rec tested and is working fine and fitted a new battery but still got same problem :-/
CosKev3 - 18/7/16 at 06:54 AMWe need a better description of what it is actually doing when it won't start,or a video.
Have you built the car yourself?
[Edited on 18/7/16 by CosKev3]
40inches - 18/7/16 at 07:58 AMquote:
Originally posted by Cadburys Man
reg/rec tested and is working fine and fitted a new battery but still got same problem :-/
Bugger!
Does the speedo work? I have got some stronger magnets.
ReMan - 18/7/16 at 12:54 PMJust a thought.
I wonder if you've got a connection (earth?) thats going dodgy, where the clutch/sidestand/neutral logic is breaking down?
CosKev3 - 18/7/16 at 11:04 PMquote:
Originally posted by ReMan
Just a thought.
I wonder if you've got a connection (earth?) thats going dodgy, where the clutch/sidestand/neutral logic is breaking down?
Yeah I was wondering that, hence why I asked if he had built the car.
Cadburys Man - 27/8/16 at 05:53 PMIt's now sorted thanks to the help from Dave aka 40Inches.
It was indeed a dodgy connection on the resistor wiring from the ignition to the ECU
