Brake Light Modulator for SV650S

This is how I fitted a brake modulator to my bike. These notes are for educational purposes only, I'm not responsible for what you do to your bike. There is a risk you could end up with no brake lights, blown fuse, etc.

Thanks to Clement over at http://www.svdownunder.com, (see this thread) I scored a brake light modulator for $20. What is a brake light modulator I hear you ask? When you hit the brakes, the lights flash a few times before going on solid. The idea is to get the attention of road users behind you (hopefully without inducing an epileptic fit).

Wiring

Now I don't read Chinese so well and my box didn't come with any English instructions. Having said that, wiring is pretty simple, about the only complication is that the SV650 I have has LED brake lights and you need to fit a load resistor to make it work. Apart from the resistor, you essentially insert it in series between your brake switch and brake light.

Note: this circuit worked for me, your mileage may vary.

I have some Yazaki crimp connectors used by Suzuki, so I just pulled out the white wire going to the brake light (check with a multimeter to be sure) and replaced it with the red coming from the unit. You need a tiny screwdriver to unlock the crimp connector before you can pull it out. I put a male connector on the black wire coming out of the unit, I also crimped in one end of a 100 Ohm, 5 W resistor into here. On the other end of the resistor I made a short fly lead with a crimp eyelet which I earthed by clamping down under the 6 mm allen key bolt near the pillion seat latch. This arrangement is shown in the picture. The resistor is covered in heat shrink tubing.

Before you make anything permanent, make sure it works. Turn on the ignition and pull on the brakes, if it flashes before going solid then it looks like it is all working.

The male spade I added to the black wire then connects with the female I removed from the original brake connector housing. Use generous amounts of heat shrink tubing on this connection and also over the resistor.

Tuck the wiring away and add a cable tie or two to tidy things up.

Mounting

The unit is quite small, not much bigger than a matchbox and you have a few options for fitting it with the supplied velcro. One easy spot is right at the back of the "toolbox". That happens to be where my disk lock fits nicely so I stuck it inside the left, rear cowling. I didn't take the cowling right off, just removed the pillion handle, nuts and clips to make enough room to get my hand in there. I cleaned up the inside of the cowling with some solvent before sticking the velcro to it.