An easy way to add a brake light to a Honda XR400R. This mod uses the existing taillight and a switch that fits the bike without modification.

Some XR's use an automotive style taillight/brake light but they don't use the brake light contact in the socket. You can tell if yours is this type by the two different elements in the bulb. I suppose they may have wired the contact that is for the brake light at the factory instead of the taillight. To check this, with the lens off, start the bike and see if the smaller element is the one that is lit, which is the taillight element. If it is thebigger element that lights,then you will need to move the existing wire to the other contact before installing the new wire.

If you remove the bulb, it is possible to tilt the socket's contacts and lift it out of the socket by pushing on the wire from behind. Then you can feed a suitable wire in from the back of the socket and solder it onto the contact that wasn't being used. After the new wire is soldered on, just carefully put the contacts back in the socket by putting in on an angle and pushing it down and pulling on the wires until the tab goes back into the proper spot in the socket. You can route the new wire through the existing harness sleeving (you just have to remove the tape at the end). If you somehow manage to break the socket, you should be able to get a replacement at any automotive parts store.

Purchase a 10mm X 1.25mm K&S Technologies hydraulic brake light switch (Dennis Kirk P/N: 21-0369) and install it on the rear brake master cylinder. It simply replaces the Banjo bolt. If you lower the reservoir below the master cylinder you will loose very little brake fluid. You will need to bleed your brake after installing the switch. Attach one of the switch wires to the new wire you ranfrom the brake light and the other to the blue wire either near the headlight or somewhere alongthe line going to the taillight. Be certain to fasten your wires with zip ties or tape so they don't interfere with the throttle or get pinched in something. Youcould also add another switch tothe front mastercylinder and connect it to the sameplaces as the rear switch. Then you wouldget the brake light with either the front or the rear brake applied.

Another tip is to put a pair of vise grips on the plastic knobs that contain the bolt heads of the taillight assembly (with lens removed) when trying to take the assembly off the fender. If you don't they are likely to crack.

With this modification you use the stock taillight and only need to purchase a switch ($15.99) and some wire. If you don't know how to solder, you will need to get assistance from someone who can, as it is the only way to properly attach the wire to the contact in the taillight socket.

Credits: Submitted by Gary and edited by 4Strokes.com

A simple way to add a brake light to the existing tail light assembly on your Honda XR!

You’ll need the following items:

• KTM brake switch with pig tail leads (P/N: 50311051100)
• M10 X 125 metric die
• 194 lamp socket (P/N:85880 or other)
• 194 lamp

Directions:

1. Cut new threads on the KTM brake switch.
2. Remove the banjo bolt from the top of the brake master cylinder and replace it with the brake light switch.
3. Cut the connector off the pig tail and connect one lead to ground and the other to a new ground wire coming from the tail light.
4. Remove the tail light cover and seat.
5. Remove the foam strip from under the tail lamp socket and sand the new lamp socket flat on each side so it fits under the original tail lamp where the foam strip was.
6. Cut the power lead (brown wire) about an 1½" from the lamp and solder the new and original tail lamp socket leads to the power lead.
7. Run a new wire through the sheathing to the other pig tail on the brake switch.
8. RTV the new socket in place.
9. Secure wiring with tie wraps and reinstall the seat and tail light cover.

For a total cost of about $30.00 and a couple hours labor you have a brake light with very little modification that can be returned to original if desired.

Credits: Submitted by Roger Ping and edited by 4Strokes.com

Update: Instead of modifying some of the parts listed above you might be able to use some universal parts sold by other manufacturers or suppliers.

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