Electrical problem

[daslex]

Hi can anyone help? I have a problem when I try to turn on my bikes lights after starting. Basically all electrics work expect headlights. When I try to turn on the headlights everything cuts out and bike wont restart until I turn the headlight switch off and then I get ignition lights and can then restart. After about 20-30 minutes riding the headlight will then work okay. As I said all other electrics work sidelight, indicators, horn and brake light. I thought it might be a bad earth or connection but it doesnt explain why the headlight works fine after 30 minutes or so

[TRPUT]

Could be the battery??? Not enough power to fire the coils and the headlight until it has run for a while and put some charge back into it.

Other than that, I would be checking the headlight switch and relay connections. A bit of heat and vibration can temporarily fix some electric gremlins.

[tone]

Thats a strange one, the only thing that comes to mind is that the wiring in the light switch on the switchgear is shorting across to the kill switch, i'd pop the switchgear off make sure nothing is trapped & see if it works with the switchgear just lightly held on to the bar
Failing that i'd look at the same 2 circuits further along the harness, checking for shorts as you go

[daslex]

Thanks guys

[Wild-Bill]

Weak battery. Check voltage at the battery.
You should have:
Engine off, ignition off - 12V or better
Engine off, ignition on - 12V or better
Starter motor turning - 11V or better
At coils, starter motor turning - 10.5V or better

If voltage is dropping past those limits then your battery is getting weak and needs replacement. You might be able to make it last the rest of the season if you put it on a float charger whenever you're not out riding. That might keep the voltage up enough to keep things working a little longer.

[jumper69]

I had a similar problem a few years ago... you might check your headlamp relay. I found that mine had a crack in the housing which allowed a build up of moisture which started making it act screwy and would randomly shut my bike down and drain my battery. Might not be your problem, but check it anyhow.