zx7r wont start with lights on

[jacko9370]

Hi
I have a 98 zx7r and it wont start if the headlights are on, if i turn them off at the switch the bike will start but when they are on the engine will turn over but not fire.
I thought it may have been the battery so got a new one and still have tthe same problem.

The lights work before the engine is running and once the engine is running

My next thing too look at would be plugs and coil but cant really understand why it would be these since it will start without the lights on.

I have fitted a alarm to the bike recently so have cut some wires but all have been reconected and the bike was having the same problem before i fitted the alarm but not to the same extent, with the lights on the engine would take a while to fire but no it just wont fire it with the lights on.


I know it is not a big deal to have to tun the lights off to start the engine then back on again afterwards is just annoying.

Any ideas would be greatly appreciated.

Jacko

[honestlyinsane]

you lost me somewhere because I cannot shut my lights off and have never seen a bike where you can shut the lights off.at least not a modern bike

[jacko9370]

is a uk/european bike with light switch so they can be turned on and off.

[xeon]

My guess is that the addition of the alarm somehow disables starting when the switch is in the on position. Otherwise the situations seems to entail that the bike is turning over but doesn't appear to be getting any spark for detonation when the switch is on. I would review the wiring of the alarm and for the bike if you have a schematic.

[jacko9370]

I dont know how it could be the alarm as it is not wired in to that system, is wired into ignition switch, indicators, and an led is not near the starting circuit.

I was reading in another forum that it could be the starter motor on its way out does this sound familiar/possible to anyone?

one other thing if i connect car battery charger then start the bike with the lights on it will work and run fine

Jacko

[honestlyinsane]

The starter would have nothing to do with whether or not the lights were on.
I would check your grounds, the lights being on could be backfeeding another circuit and taking away its ground.
If you know how to do it the best way to tell is a voltage drop test.
even if your grounds are tight they may not be clean.
Or the cable(S) itself could be bad