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ZX9R - Flat battery, starts when jumped but then cuts out
MK9R - 31/8/08 at 07:44 PM

A few months ago i got to a trackday and the battery was totally flat, (The car ran fine a few a couple of weeks before). I jumped started it, but as soon as i disconnected the jumper lead the car cut out. I borrowed a battery for the day and the car was fine so i assumed the battery was buggered. I bought a new battery and all has been fine for a few months, then on Friday the same thing happened (car was fine the sunday before). So now thinking that the battery isn't charging, what do you think??

JoelP - 31/8/08 at 07:50 PM

have you checked charge voltage when running? Im thinking the reg/rec is much more fragile than the generator.

MK9R - 31/8/08 at 08:33 PM

Need to do that, but float chamber got stuck open at the end of the day so fuel is peeing out of the carbs, i need to strip them down first. How will i know if its the generator or the rec/reg?

Hellfire - 31/8/08 at 10:05 PM

Sounds like a rectifier problem but I've not heard of one going down on a ZX9 before...

Steve

MK9R - 1/9/08 at 06:49 AM

quote:
Originally posted by Hellfire
Sounds like a rectifier problem but I've not heard of one going down on a ZX9 before...

Steve


bugger, fingers crossed i can get a cheap one to test it!!

MK9R - 1/9/08 at 06:53 AM

Just remembered, when i used last before the battery was flat, speedo back light kept go dim and bright, then the speedo stopped working all together. When i jumped it (and left the battery connected the speedo was reading 110mph. When i put the new battery on it worked perfectly.

rectifiers are cheap on ebay, so going to get one, it will be useful as a spare if it turns out to be something else.

Peteff - 1/9/08 at 08:48 AM

Bike batteries will not stand long periods of inactivity and will not come back to life once flat, they need to be trickle charged. The bike engine will not run on a dead battery after the jump battery is removed. Spend some money on a charger like an Optimiser that can be left connected when the car is stood after you have sorted it out.

MK9R - 1/9/08 at 09:07 AM

quote:
Originally posted by Peteff
Bike batteries will not stand long periods of inactivity and will not come back to life once flat, they need to be trickle charged. The bike engine will not run on a dead battery after the jump battery is removed. Spend some money on a charger like an Optimiser that can be left connected when the car is stood after you have sorted it out.


It was only 5 days, although the kids had been playing with the lights, so suspect they had left them on.

Not sure what to do now, it may just be a flat battery then??

JoelP - 1/9/08 at 08:39 PM

simple, do whatever you need to do to the carbs, then new battery, then start with a volt meter on it, measure voltage at idle and through revs, if all seems normal (ie 14ish volts), take it for a lap of the block with the volt meter still on. Someone said that a buggered regulator can lead to 400V being sent to the battery id guess yours is not more than 20V or youd be blowing fuses, but that would still upset the battery.

Or maybe quicker and cheaper, connect the battery off your tintop so you can check voltages.

[Edited on 1/9/08 by JoelP]