headlamp & tailight keep blowing..!!!

[cheesecake]

Hi,

Stripped the plastics off to check wires and for damp/chafing/shorting etc. Can't find anything obvious.
I thought maybe bad earth/loose wire/water shorting it out etc. Traced n checked all wires, all seem OK.
Sprayed all plugs with wd40 to drive out any moisture but a long shot as all seemed dry n well placed out of the way of any rain/water spray.
Its just headlamp n taillight, indicators, brake light n all other lights/electrics are unaffected...??
Put a new bulb in, fire engine n it blows within seconds...!!
Voltage regulator..?? But why does nothing else blow..??
I'm stuck, any help or pointers  greatly appreciated.
Thanks.

[tortoise]

Voltage regulator..??

[zombie]

The headlamp, and tail lamp are both AC fired, and do not go thru the regulator. so that's not it.

Have you changed the Stator by any chance?

If the wiring going to either of those light gets grounded then the bulb takes a full 1/2 sine wave of whatever voltage the AC side of the stator puts out. I THINK it is around 235 volts AC peak. The reason these 12 volt bulbs can survive is they only see 1/2 sine to an open circuit using the resistance of the charging coil as a make shift ground. Sounds like a lot but it's pretty simple...
if the stator has a shorted coil this will also make the bulbs blow instantly.

If you have altered nothing...  remove both bad bulbs, Disconnect the stator plug, and test each of the wires for a short to ground on the bike. If they show good then test the stator as per the manual... http://www.kymcoforum.com/index.php?topic=495.15  It's about 1/2 way down that page.

If the stator proves bad:
Look at the left side/bottom of the engine (below the CVT cover) for a section of the engine case that has the engine ID numbers. It is either a kg 10 sa, or a qmb 139. Post the number, and we'll help find the part for a good price.

[cheesecake]

Cheers zombie
I'll get on it and report back 

[blue]

Clean all the conections to see if that helps. Even the stator conections.

[cheesecake]

Tested stator wires and coils, all seems good.
Then I went to test the regulator/rectifier behind the headlamp shroud and it wasn't there...!!!
I have a plug with a 4 spade connection that are very clean so no corrosion tells me its not been missing very long....
I can also see the threaded stud next to the horn where I presume it was once fastened to...!!!

Can anyone help with part number/somewhere to buy a replacement..??
Thanks

[zombie]

Stadium Yamaha. The regulator is in the Wiring harness section. Just follow the breadcrumbs starting at Kymco Parts.
Call in your order, and get the forum 15% discount.

They are listed on Ebay but are Taiwan order. partsforscooters also sells one but it is a GY6 engine type so it will not work for you. OEM is the best way to be sure you get the right one

[blue]

Try this.

[MoToFaLcon]

Try this.

Yeah! Try that!

[zombie]

All joking aside... rewiring, and using LED's, and DC voltage is the easiest route. I switch them all when there is a lighting issue. WAY cheaper in the long run.