Introduction to installing your new LED rear light unit
Installation of our new LED rear light boards into a Lucas 564 rear lamp is very simple. The new version does not require any modification of the rear light unit; the LED board just plugs straight into the socket just like a conventional bulb.
The procedure is exactly the same regardless of whether you are installing a 6 or 12 volt unit and irrespective of whether the bike is wired positive or negative earth.
If you have one of our original Lucas 564 LED boards (the type that requires two holes to be drilled in the back plate of the lamp unit), then please see here for the original installation instructions.
Installation guide contents (click to jump to a particular section):
- The tools you will need
- What’s included in the kit
- Step 1 – Removing the rear light lens
- Step 2 – Removing the old filament bulb
- Step 3 – Installing the new plugin adapter
- Step 4 – Mounting the LED light board
- Step 5 – Testing the brake and tail light functions
- Step 6 – Reassembling the Lucas light unit
- Conclusions and your comments
The tools you will need
To complete the installation of the LED rear light board you will need the following tools and equipment:
- Screwdriver (to remove the red plastic lens)
- 2.5mm Allen (hex) key to screw the LED board to the plugin adapter
- 7mm spanner to hold adapter whilst the screw is tightened (optional)
A spanner and Allen key installation tool kit are available for purchase at minimal cost along with the LED board kit if you don’t already have these available in your toolbox.
What’s included in the kitThe various components included with the LED light board kit are as follows:
- 1x LED light board of your chosen voltage rating (6 and 12 volt versions available)
- 1x BAY15D (1157) plugin adapter and LED board mount
- 1x M4 screw (to attach LED board to the plugin adapter)
- 2x M4 plastic insulating washers (to go either side of LED light board)
Unlike with the original version of this LED board, this new version does not require any modification of the rear lamp unit. The LED board is completely plug-and-play and you can swap back to a conventional bulb at any point if needed.
Step 1 – Removing the rear light lens
The first step is to remove the red plastic lens from the lamp unit, just as if you were going to change the bulb. After removing the two screws, the plastic lens can then be carefully removed. Take care of the rubber seal that fits between the lens and the back plate (if fitted) as this may stick to one or the other side.The fixings that hold the lens in place tend to vary between different versions of the Lucas 564 lamp unit. The original Lucas units (as well as the modern genuine Lucas reproductions) featured two fixed screws that protrude from the lamp’s back plate. The lens fits over the two screws and a pair of sleeve nuts fix it in place.
However with most modern reproduction versions of the Lucas 564 style light unit, the lens is held in place by two long screws which go through the red lens and screw into the lamp’s backplate.
The LED board has been designed to be a universal fit and work equally well with all versions of the Lucas 564 style rear lamp unit whether they are original, genuine Lucas reproductions or unbranded pattern parts.
Removing the old filament bulb
With the lens removed, the standard filament bulb can then be removed. The bulb has a bayonet style fitting so in order to be removed it should be gently pushed inwards and then rotated anti-clockwise to release.Take a look at the bulb once you have removed it and in particular the two ‘pips’ that protrude from opposite sides of the base. One of these pips should be slightly higher up the side of the bulb’s base than the other so that they are offset. This prevents the bulb being inserted the wrong way round and the bulb filaments getting reversed (so that the brake light comes on when the tail light should, and vice versa). This type of bulb fitting is referred to as a BAY15D or 1157; this is the style of adapter that is supplied as standard with the LED board kit.
If the two pips are at exactly the same height then you have an unusual BA15D fitment rear light. These are quite rare; I’ve only come across one cheap replica light unit in India that had this fitment. However BA15D style adapters are available for the LED boards just in case, by special order. Please send me a message (just reply to your order confirmation email) to arrange a swap if required.
More information regarding the various different types of bulb fitment can be found here.
Installing the new plugin adapterThe plugin adapter supplied with the LED board kit plugs into the lamp socket in exactly the same way as installing a conventional bulb. Insert the bayonet fixing, push gently inwards and then rotate clockwise to lock in place. It is easiest to grasp the adapter via the metal mounting post.
If the adapter will not rotate in the socket, check that you have it the correct way around and rotate it by 180 degrees if necessary. Remember that the two ‘pips’ are offset to each other at different heights to ensure that the tail and brake light functions and connected the correct way around. The adapter will therefore only plug in one way round.Once the plugin adapter is installed, grasp the metal mounting post and try to move it gently from side to side. It is important that the mounting post sticks out perpendicular to the back of the lamp unit. On a couple of rear light units I have found that the bulb socket isn’t very well formed and is therefore a little slack allowing the bulb (or in this case the plugin adapter) to move from side to side.
If you notice that the plugin adapter feels lose or is angled to one side, it is worthwhile taking a few moments to correct this so that the LED board sits square to the rear light. The easiest way to do this is to using electrical tape (or similar) stuck to the appropriate side of the plugin adapter to provide the necessary padding. Ironically it seems that the newer cheaper reproduction lights are better made in this respect that the original Lucas units!
Mounting the LED light boardWith the plugin adapter installed, the LED board can then be mounted. Firstly make the electrical connections by plugging in the wires from the adapter into the back of the LED board.
The electrical connection is designed to be tight so that it doesn’t come lose with the vibrations from your bike, so please take care when plugging the LED board in. It may be necessary to hook the socket on the end of the wires gently under the plug on the back of the LED board and lift slightly to line up the pins.
Make sure you have the plug the correct way around. The flat side with three small holes should face outwards (away from the LED board) and the side with a ridge along both edges goes towards the LED board.Arrange and bend the wires as necessary to be able to position the LED board against the mounting post which protrudes from the plugin adapter. You can wrap the extra wire around the mounting post or else just bend it so that it sits to one side or the other. Either way, ensure that the wires do not get trapped between the mounting post and the LED board as it is tightened.
The LED board kit is supplied with a M4x10mm long mounting screw and two plastic insulating washers. One washer is fitted either side of the LED board. It is usually easiest to put one washer over the screw, push this through the hole in the centre of the LED board and then put the second washer onto the rear. The LED board and screw can then be offered up to the mounting post and tightened using a 2.5mm Allen key.Gently nip the mounting screw up and then check alignment of the LED board with the rear light unit. It needs to be carefully aligned so that the red plastic lens will fit back over the top. As you tighten the screw, you may find that the LED board has a tendency to rotate in the same direction, in which case you will need to carefully hold it in place at the same time.
To tighten the LED board once it is in place, hold the plugin adapter steady with a 7mm open-ended spanner over the mounting post. This will stop the adapter rotating in the socket whilst you tighten the screw with the Allen key. The screw does not need to be over-tightened as the plastic washers will squash slightly and provide a locking function.
Testing the brake and tail light functions
Before reinstalling the red plastic lens, it is worthwhile testing the tail and brake light functions. Start by turning on the motorcycle’s headlight and verify that the four red tail light LEDs and the three white number plate LEDs illuminate. Turn off the headlights and apply the brake checking that the all of the LEDs turn on. (Note that for positive earth motorcycle’s, the tail and brake light functions are not linked so that eight red LEDs will illuminate when the brakes are applied. For the standard negative earth motorcycles, the tail links are linked to the brake light so that all LEDs will come on when the brakes are applied, irrespective of whether or not the headlights are on).In the unlikely event that the tail and brake light functions are reversed (i.e. the tail light LEDs come on when the brakes are applied and vice versa), then the wiring to the tail light of your bike is reversed for some reason. The easiest way to rectify this is to swap over the orange and red wires in the plug that fits onto the rear of the LED board.
Unscrew the LED board and carefully unplug the wiring connector. Tilt the plug slightly upwards as you pull it off the circuit board connector to release the locking tab. Also unplug the adapter from the rear light unit.On the flat side of the plug you will see three small holes; these are where the internal connection pins lock into place. To remove the orange and red wires from the plug, insert a small needle into the respective holes to gently push the locking tabs inwards. By applying a small amount of pressure the wires should then pull out.
Take great care when doing this as the internal pins are quite delicate and pushing too hard with the pin or pulling too hard on the wire is likely to deform them. The wires should pull out very easily once you have correctly released the locking pin with the needle.
Insert the red and orange wires the other way around and then reassemble the LED board as described previously. The tail and brake light functions should now be reversed and correct for your motorcycle.
Reassembling the Lucas light unitWith the brake and tail light functions tested, the rear light can then be reassembled. Carefully place the red plastic lens over the LED board and ensure that the wires do not get trapped under it.
Insert the fixing screws to complete the installation. For rear lamps that come with the long screws which screw into the lamp’s backplate, it is helpful to align the lens first by looking through the holes. Otherwise it can sometimes be tricky to find the screw holes if the lens is offset to one side. Also check that the rubber seal behind the lamp is correctly positioned and not twisted so as to prevent water getting inside the lamp unit.
Just a final check that everything is still working and the installation is complete. It is a simple job to swap back to a conventional bulb at any point if needed, although we’re not sure why you would ever want to do that!
So that’s the installation complete and your new LED rear light board ready to give you many years of bright service. If you have any problems them please do not hesitate to get in touch using the contact form at the bottom of this page. Please make sure your email address is correct so I can get back to you.
I would also be glad to hear how you found the installation process, any problems you encountered or anything that wasn’t clear or missing from this installation guide. Please let me know how I can improve the guide by leaving me a reply via the comment form below.
Hi, I have a ’63 Tiger cub and the 6v rear bulb keeps blowing. Will installing LED conversion stop this or will LEDs blow too? Thanks, Rob
Hi Rob. Most standard LEDs will have the same problem as your filament bulbs – it sounds like you have a problem with your regulator. However our special LED boards described above have protection circuitry and can withstand much higher voltages. The 6 volt version is fine up to 9 volts or more. I’d recommend fixing the problem though rather than just trying to work around it. Regards, James
A bit of feed back on your light fitting,very easy to fit and works well just fitted it to an original 564 unit a little bit of adjusting to sit it in the right place not unexpected with these old Lucas units the bulb holder on mine had turned slightly and just needed realignment, good design well made,couple of observations the centre bolt hole needed filing out slightly to clear the swarf, and it might be an idea to have two holes in the reflector rather than cut outs for the lens mounting bolts,perhaps two oversize brass eyelets to aid alignment. Hope this helps cheers Steve.
Hi Steve, and thanks for the feedback, that’s useful. The reason I went with a contoured LED board (rather than having two holes to accommodate the lens fixing screws) is that unfortunately there is some variation in screw position between the various original Lucas, repro-Lucas and cheap copy lamps. The contoured board accommodates all types, whereas I was concerned that holes (even over-sized ones) might not.
Trying to the bulb base aligned correctly can sometimes be a bit of a pain with original lamps as the bulb holder and contacts aren’t always too precise, or are worn. I needed to do similar fiddling with the lamp on my own Matchless, but once its in the right place, you shouldn’t need to ever touch it again!
Just installed the brake light — WOW! What a difference, it is bright!
The install went pretty much like the instructions read. Everything fit as described. My ’09 had course threads rather than fine as on the posts, but it wasn’t a problem. Space is tight to get at the wires and I did unbolt the tail light housing for easier access.
I totally endorse this kit!
Thanks Alex. Glad you’re pleased with your new LED rear light 🙂