Mystery power drain / starting problems

[helloindustries]

So here it is: If i run the bike with a set of M&P dominator-like twin lights, then stop the bike, then try to re-start it; I get nothing other than the sound of a dead/dying battery.

Battery is very recent/tested/OK
Reg/Rec is new/tested/OK
Magneto is tested/OK
Charge rate is good at idle(approx 1k)/2k/4k revs
Starter and coils are OK

All i can think of is that either the lights are a MASSIVE power drain, or that there's some other problem.

[Fazafou]

Was it after fitting the lights you noticed the problem, and only when they've been on?

Could be a short in the circuit somewhere. The lights themselves wouldn't be a drain.

What's the voltage when running with and without them on?

[helloindustries]

No info prior to current lights as it was a rebuild from write-off. As for the other specifics: I don't currently have that info.


I guess i should un-bundle the front light/indicator wiring and check that.

[Fazafou]

Ah, rebuild could have a dodgy connection anywhere, yeah best to check it all out for a short etc.

[helloindustries]

Culprit is likely the headlight wiring which i have cunningly bundled with various other wires behind the lights/under the instruments in a classy ball of electrical tape in lieu of taking the time to fit it all under the forward part of the tank in the gap there, then extend wires to fit neatly (leaving extra length for probable changes of headlight).