Modifying the bicycle lights to LEDs, working off the 24 volt batteries.

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First of all the lamp was removed from the bike and dismantled. 

The trickiest part was separatiing the fragile lens from the body.

 Here are the tools I used.

The modified body parts.

A hole was cut in the reflector allowing the lamp to pass through.

Testing the assembly and checking the fit before glueing the parts together with superglue. 


Fit sleeves over the crimp connectors on the cable. 

Fit the lamp connector, mount the rear cover & connect the cable (push fit) 

I have now mounted the modified light onto the bike.

The lamp is rated at 12 Volt Ac or DC, 1.3 to 1.5 Watt. I connected it to the 24V battery through 3 off 374 ohms resistors in parallel to give a current of 104 mA and 15V across the battery. This means that the lamp is using 1.56 Watts. A little over the top but no problem on an overnight soak test. (but see the revised modification below)

Photo top left:
Lamp now connected through the rear using the original connectors.

Photo top right:
Early dusk. Shows both the LED Cateye Opticube lamp on the bars tilted down for normal use and the modified lamp below used as an 'always on' running light.

Photo bottom left:
The beam pattern shown onto the garage door with the Cateye tilted up. The Cateye gives a sharp pattern where as the pattern from the modified lamp has a more diffused edge.

Photo bottom right:
Shows the two lamps shown from the front with with the Cateye tilted up for comparison. I must admit that the light from the modified lamp is better than expected so I am well pleased with the project.


Revised Modification.

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As I was not happy with wasting energy by using resistors in the circuit, I decided to use components from left over from other jobs to light up the original rear lamp on the bike. 


First of all I removed the rear light, opened and cut off the bulb holder using a soldering iron. The backplate was then cleaned up, a grommet fitted in the hole, the hood cut off the Kingbright light cluster which was then fixed to the backplate.

 The cluster was then wired to the rear lamp leads, the rear light reassembled then re-mounted.

The rear lamp was then wired in series with the front lamp through and connected to the bike battery though a switch and an inline 2A fuse. The measured current varied between 95 & 100mA.

The new rear light is not quite as bright as the Cateye lamp below it. The new LED front lamp is very satisfactory. 

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