bike fine, turn on lights and dies

hi guys,
i have trawled through posts on here and i cannt find a definitive answer to my issue.

the bike is a 99 and idles a treat, charges at over 14v and is generally fine...............until you turn the lights on, then the voltage (at the battery) drops and after about 10 seconds the bike stalls and wonnt start. turn the lights off and voila , the bike starts and runs fine until the lights go back on.................any ideas chaps?

i have a new battery on it.............

What does the voltage drop to when you turn the lights on, and what happens if you remove one globe so only one headlight is on?

Does the clock revert to 1:00am?

Suspect R/R.

hi guys,
i seem to think in the past that it did revert to the default time, but since i put the new battery on it just stalls and if i turn the lights off i can fire it straight away.
strangely i have just done a run , got it home and turned lights on and it donnt stall, yet it did when i first set off.
i will measure the voltage later and report back. i am wondering if its the rectifier?

hi guys,
i seem to think in the past that it did revert to the default time, but since i put the new battery on it just stalls and if i turn the lights off i can fire it straight away.
strangely i have just done a run , got it home and turned lights on and it donnt stall, yet it did when i first set off.
i will measure the voltage later and report back. i am wondering if its the rectifier?

It sounds like it is. Make sure you replace it with the upgraded one from David Silver Spares. :fing02:

i will measure the voltage later and report back. i am wondering if its the rectifier?

Simple test for this. Unplug the regulator from the wiring harness and start the bike (also unplug the stator from the regulator). Make sure your battery is fully charged first of course, but if your bike dies when you turn the lights on then, it's not the regulator causing your problem.

great advice! will try
what colour wires go into the regulator plug and the stator .....?

great advice! will try
what colour wires go into the regulator plug and the stator .....?

One connector block with three yellow wires - stator
One connector block with two red, two green (and possible one black) wires - Regulator.

Unplug all of those and test.

update!!
ok i disconnected the plugs one by one leaving one connected and then swapping.
it does not matter which is connected or disconnected the bike stalls and when you turn the headlights on (to make it stall) there is a noticeable drop in engine revs........
am i too assume that the r/r has had it?

I had a similar problem until few days ago when I've installed a VFRness and placed the headlight's on different circuits from the original (directly to battery via their own fuses). VFRness bundle comes with a second circuit (accessories fuse panel kit). On my bike this kit is controlled to power on with an engine running sensor (from a Cheetah remote/HUD - but it can be replaced with an http://www.wiremybik...products_id=690) so that headlights will not turn on until engine is running. For now I didn't experience problems but is too short time to tell...

update!!
ok i disconnected the plugs one by one leaving one connected and then swapping.
it does not matter which is connected or disconnected the bike stalls and when you turn the headlights on (to make it stall) there is a noticeable drop in engine revs........
am i too assume that the r/r has had it?

Beginning to sound like it. Which model is the current one? If it's the OEM one, I'd just grab the upgraded one and fit that and see.

When my R/R died on my Fi-W, it ended up cutting the engine out every time I indicated, so it went run....stop.....run......stop.......until I got it to the dealer.