Halogen headlight blowing

Hey there... My bike has had one of those dual "dominator" halogen headlights since I bought it. I've never really liked it since I'm a fan of the classic round lights, so I finally bought a single halogen kit and installed it.

The problem is now the bulb blows the second I rev the engine much past idle. My first thought was R/R over voltage (which I will check with a multimeter in the morning), but since all the other lights are fine I'm not sure that's it. Since the bike has been running halogens since I picked it up over a year ago, I'm not sure why that would be an issue with the switch, running the same bulbs. Could the dual headlight rig just absorb the voltage better?

The other theory is vibration, but this happens almost instantly on revving while stopped, and vibration doesn't seem all that high to me. I've now blown two bulbs and want to figure this out before I waste the two I have left. Any ideas? Thanks.

Measure voltage on the battery posts.
Measure voltage on the headlight two ways. At the bulb wires (+ and -) and then bulb wire + to battery negative post.


This could possibly be a broken ground connection somewhere or a bad connection in the switched 12v system (brown wire, usually).

Thanks for the reply. I finally got around to checking this today. To be extra sure I used rubber grommets to dampen any vibration and hard wired the ground connection. Despite that, everywhere I checked I was getting up to 20+ volts when revving which leads me to believe.... my Reg/Rec is fried after all

That being said, does anyone have any experience with those ElectroSport RRs? They have one that looks like a direct replacement for my bike for $70...

I've recommended their products to other riders, but they also have a troubleshooting page.

Before you pony up for a new R/R assy. Do as Loudhvx suggested, check the R/R ground. That's the Black/ Yellow wire. It must have a good connection, as this is where the extra voltage gets shunted back. Also if yours is the 6 wire R/R then you have a Brown Voltage sense wire, again Loudhvx mentioned this. It must be nearly the same as battery voltage,but it is Switched through the ignition etc. A voltage drop on the brown wire, will cause the R/R to make up the difference, thus overcharging the battery.