LCGB Forums

Hello. Am out on the scoot and I've no lights to get home! I've replaced my speedo and the wire for the speedo light is attached by a proper screw joint (like that on a household plug) whereas on the old one, a wire was attached to the bulb. There is a double earth wire attached to the headset and the bulb screw. I've obviously messed something up as the lights were working before. Any ideas chaps? Btw, I've no brake light or horn either

Hi

Last time I lost all lights/horn it was the wire from the stator to the regulator that had snapped at the connector (elec ignition). Would be worth a quick check that all wires are secure

Tony

Have I got this right, you have a new speedo and speedo bulb holder? the screw type you describe uses the bulb holder to earth out via the speedo. Trouble is most speedo are plastic so dont earth. That would not knock out your lights you would not have a speedo light. The screw you described shorted out to the head unit would though. Whip the headset off and loose the speedo bulb holder and make sure any earths are connected to ground and not floating around. To use the bulb holder you have you either solder a wire to the side of the holder as a ground, or splay some copper wire out and wedge it in with the holder into the speedo. you need to make sure nothing is touching that pesky screw.

From my own vehicle experience whether cars or scooters, if a sectioned light fails its usually the local earth to it or the positive line has broken in between switch and device, if all the lights have failed its usually a general earth or a main live feed problem, the mentioned stator wire problem is usually the cause of such as yours on a Vespa where the stator out grommet has broken and the wires have chafed, another area for Vespas was at the steering joint where chafing would cause merry hell with the loom, could that be an issue on a Lambretta?

MK Monty has it I recon, that screw terminal you mentioned will be long enough to just contact the top of the fork tube. It isn't the earth wire, it is the live feed to the speedo light and if it touches earth you will loose all lights as it will short the entire lighting feed. Do as Monty suggests and the problem should go away.

Sorry I didn't spot this yesterday

Thanks to all. I disconnected the earth wire that ran from the headset to the speedo bulb and, Hey Presto, all lights back!!! Yet this WAS connected to the old speedo bulb. Weird

B*gg*r - wrong again!

Tony Hart wrote:B*gg*r - wrong again!

Very valid check though and easier than removing the headset.

Especially at 11:15 at night!!

No Crystal ball just had the same thing. I broke the screw terminal out of the bakelite and soldered a wire direct on the end of the bulb with an earth wire soldered onto the rib of the bulb holder. The bulb I used was a LED so its still going strong. To many shit lighting products with poor plugs and sockets or terminals, all just breakdowns waiting to happen so I tend to be a it anal about soldering everything. Glad you are going