Where can I get a flashing brake light?
1. Kisan makes a product called the tailBlazer, which will make your brake flash on and off when you stop. It works in much the same way as a headlight modulator. For the EX250, you want model #100HD, which plugs into your wiring harness, or the #10W-D, which is a replacement bulb with a built-in modulator. It's plug-n-play, but you have to use their replacement bulbs.
2. Another option is the Signal Dynamics Brake Light Signal Module (models Back Off and Back Off XP). It's considerably cheaper than the Kisan, but has some assembly required, whereas the Kisan is a five-minute plug & play. Wiring instructions are quite simple, and are included on their web site. If space is an issue, then go with the Kisan. The Signal Dynamics units are 2-1/4"L x 1-5/8"W x 5/8"H.
This video shows the Signal Dynamics Wig Wag module. This one is made for two brake lights, which is possible because the owner installed extra brake lights in the pods. This model has two modes available: Flash sequence followed by a steady brake light, or a repeating flash sequence. This shows the steady lights. If you want to restart the flashing it's merely a flick of the fingers away.
3. Comagination sells brake light and headlight modulators. These can be configured in several different ways.
4. You can put Hyper-Lites (LED modules with flasher) in the extra pods. You can see the installation and a demonstration here. They're very effective, plus they give you extra running and brake lights if your incandescent center bulb goes bye-bye. $80 or so shipped. Get the generic dual-function model (for running and brake lights) from this page. They may not be as easy to install as the Kisan, but they're cheaper and provide a number of additional benefits.
For installation in the two spare pods, it's recommended to undo the two bolts holding the rear taillight on the bike, and install the Hyper-Lites with the light assembly off the bike. It's a very clean installation; you can hardly tell it's there until the extra lights come on.
Check the other pages in Brakes, and also in Electrical & Lighting, for more ideas on how to make the rear of your motorcycle more visible.
This report covers the installation of a Signal Dynamics Back Off Module. For this installation, the modulator was installed on the wiring harness (front) side of the rear light assembly molex connector. This was due to the location chosen for the unit, and also so the taillight assembly could retain plug-and-play removal.
The modulator has two wires that won't be used. Add heat shrink and/or crimp connectors to them and seal them from the weather.
Next, add connectors to the three wires which will be used.
These connectors come with heat shrink tubing pre-installed. If the ones you get don't have this, find some separately.
Follow the Signal Dynamics directions (from their website) to connect the wires. The connections are slightly different, depending on how you want the lights to flash. Use the wiring schematic if you need help. What you really need to know is that, on the EX250, the blue wire goes to the brake light, the red wire is the running (tail) light, and the black/yellow is ground (always).
Use double-sided 3M tape, zip ties, or something similar to mount the modulator, in this case on the right side of the rear fender.
This unit works just like the Kisan unit, at 1/3 the price. The trade-off is that the Signal Dynamics unit is bigger. The 250 has ample room for the larger Signal Dynamics unit, while space is more of a premium on the 650R, shown here with the Kisan unit.