Lights not working

Previously wrote:

Hi Jake,

If the instrument bulb holders only have a single ( feed ) wire then the earth relies on a good contact on the instrument body, if the bulb holder is corroded then there may be a bad earth causing the problem. You could try cleaning / abrasing the bulb holder / instrument body contacts or purchase a two wire bulb holder and connect the earth side directly into the multiple earth bullet connector in the headlamp shell. Alternetively you could try soldering a separate earth wire ( red ) onto the metal part of the bulb holders and wire up as described.

If you are only getting 6v between your bulb holder contact and earth then you obviously have a problem, check the feed at the connector in the in the headlamp shell and the earth directly on the red wire connector, if this is 12v then check at the bulb holder again and the red earth wire in the headlamp shell, if this is 12v then you have a bad earth on the bulb holder / instrument pod and this can be rectified as described above. If however it still reads 6v then it is the bulb holder feed wire or corroded bulb contact, either way new bulb holders would be required if cleaning the contacts does not cure the problem. Oh I know this is obvious, but check the bulbs first!

Previously wrote:

77 Mk 111 Commando - Both the rev counter and speedo lights don't work, tried everything to no avail.

The pilot light did not work either, on removing the headlight assembly, the RED earth wire was not connected to earth (Bullet connection on pilot light holder) - now working - Any ideas about the ones above, there is 6 volts in the holders for both lights - I take it there should be an earth for them to work but don't know where the earth is.

Any info appreciated.

Thanks

Jake. hello well make your own earth , drill a small hole at the back of your speedo and rev counter too that a small screw and have wire with a eye-let on the end and fit them too the back with the two screws and take the wire in head lamp to the earth point then you should a light ? if not then you have a broken wire some where ? yours Anna J

This motorcycle came out of the factory with working instruments lights, hence you do not need to drill holes and add eyelets. You need to look at the lamps holders and correct the fault. There should not be 6V anywhere on a Commando either. 12V!

Al Osborn