Friday 5 May 2017



I was not going to add lights as it is mainly going to be used for car trials. However running it on the road would give me the advantage of testing for reliability outside track days. I feel I need road legal lights. I did a 12V conversion on the generator/regulator and I am using a race battery with limited capacity so I converted all the lights to LED. The battery will not take a charge till above tick over and there is a lot of tick over/starting at car trials. The headlights are 1938 pattern "King of the road" Lucas 4 1/2" headlights. There is no way the generator will support conventional 2 x 35W headlamp bulbs, so I sourced a 2 x high power sop/ tail LED bulbs. The low power (tail) acts as dip and side lights and the high power (stop) gives me main beam.

The indicator pods had 21W bulbs but now have 2W high intensity LED conversions.


The rear was a little more tricky to fabricate, but a lump of cardboard, a box bender, and a little welding att the corners produced the necessary assembly to hold the number plate and lights. The light units are LED indicator + Stop/Side variety are from a vintage motorcycle dealer on ebay. The number plate light was fabricated with a right angle fabrication and a 300mm waterproof LED strip from ebay.

Brake lights

I had a tad of a problem getting the brake lights working despite having all the original hardware so I thought the following worth mentioning. The brake light switch did not align with the tab on the actuating rod. This adverse angle resulted in stiction being applied the switch assembly resulting in the lights staying on after applying the brakes (hysteresis). I had to make an extension to the attachment tab to ensure alignment (and therefore minimising the stiction). I also found the spring tension was critical, I used a brake shoe spring.


I now have a viable lighting setup that will not flatten the battery while ticking over. All side lights (4) take 0.33A or 4W and the side + headlights 1.5A or 18W total. This compares with incandescent lamps which take 20W and 70W respectively.

Update 4th Aug 21

The major change was a) Fitting an alternator b) The headlights have been upgraded with Vespa inserts to comply with the MoT requirements.

Here is an Index page for the build

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