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California Scientific

California Scientific
1000 SW Powell Ct
Oak Grove, MO 64075

Motorcycle Headlights and Tail Lights

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Standard 55w/65w 9003 halogen bulbs are available at any auto parts store for about $8 each. For about $15 or so, you can get alternative wattages like 65w/80w or 80w/100w. Personally, I don't care for these bulbs. They tend to be quite fragile and break easily from vibration. They also happen to be illegal, although it's hard to imagine a cop checking your headlight wattage.

Xenon charged halogen bulbs are considerably brighter. There's a lot of advertising talk about 4000 degree temperature equivalents. It's marketing nonsense - what you care about is lumens (light intensity), not color spectrum. The blue tint on the glass of these bulbs is to absorb much of the yellow light, and make you think the bulb is whiter (hotter) than it is. This is actually bad for us: the reds and oranges penetrate fog twice as far as the blues, so the blue tint means these are terrible bulbs in fog or rain. But, the xenon gas charge means they putout about 20% more light for a given wattage, and that's a good thing.

HID bulbs are even better for putting out light, but they require a bunch of electronics to produce the 18,000 volts they need to work, and are quite expensive. In 2003, they're about $350 per bulb. I won't be putting $700lights on my motorcycle anytime soon. If you do, please email me and tell me how they look. Be sure to use the phrase "Better than sex."

APC Xenon Light Bulbs
APC Xenon Light Bulbs. 55/60w, $30 per pair.

Philips Vision Plus
checkmark Philips Vision Plus.55/60w, $28 per pair. Not DOT legal, but that's because they haven't been certified. These bulbs are perhaps very slightly brighter than the sylvanias, and the sylvanias are slightly whiter. Overall very comparable.

Sylvania H4 ST, $50/pr. These bulbs are available from any auto parts store as 9003 ST for cages, and as H4 ST which are heavy duty for motorcycles. You'll likely have to special order the H4 STs. I use these, I think they're fantastic. They are a huge improvement over the stock bulbs, which I consider marginal at best. Don Huntley and I both run these bulbs, and both of us lost a left side low beam at about 14,000 miles. It seems ST1300s are particularly hard on their left side headlight bulbs.

White position lights to match your Philips or SilverStar white bulbs are available at You want PIAAX-treme 3156 bulbs, about $17 each.

Kisan Pathblazer Kisan Pathblazer
Kisan Pathblazer P115W-Dual Headlight modulator, $150. Includes photocell for automatic night disable.

Headlight Modulator
Signal Dynamics Headlight Modulator with photocell sensor for automatic night disable and dual headlight kit, $94

Headlight Adapter Shims Headlight Adapter Shims
Headlight Adapter Shims to use 9003 bulbs in some Hondas, $12/pr. part number00507. Honda uses a proprietary 45/45 watt bulb which has three tabs like a 9003, but at different positions. These bulbs are used in the ST1100 / 1300, VFR750/800 and Goldwing 1500s. The bulb shown above is a 9003 with the shim mounted, showing 5 tabs instead of 3. You must trim off the bottom 2 tabs so that the bulb will fit into the housing.Without the shim, the bulb angles up instead of pointing straight ahead. If you lose a headlight bulb on the road you must get a $$$ replacement at a Honda shop, or own some of these shims. Also available a

Tail lights

Custom Dynamics makes LEDlights for motorcycles, both custom and replacement.

Clear Stop Light Lenses
Clear Stop Light Lenses from ClearAlternatives. $50 - $75, plus you need new red bulbs.

Kisan TailBlazer
Kisan TailBlazer 100HD taillight modulator, $85 ea.

Brake Light Modulator
Signal Dynamics Brake Light Modulator $35.

Brake Light Modulator
Brake Light Modulator $20. Causes the illumination of brake light to pulsate from bright to dim approx. 5 times per second. Small (approx. 1" x 1-1/8" x 1-3/4") control module mounts in any convenient spot. Installation requires cutting of brake light wire, installing terminals on cut ends and plugging in to pulsator. Circuitry is water and vibration resistant. Includes connectors and instructions.

HyperLights HyperLights
HyperLights LED brake light augmentation. $55 - $75. 16 LEDs flash brightly when you hit the brakes. Mount with double-stick tape. Reportedly very bright.

BackOff LED License plate frame
BackOff LED License plate frame - about $60. Available in black or chrome, with one, two, or four LED light bars.

Kisan turn signal canceler Kisan turn signal canceler
Kisan turn signal canceler set to make turn signals act also as running lights; BackOff LED license plate frame; TailBright reflective stickers on saddlebags (note surface texture). This makes a huge difference in rear visibility. Photos by Charlie Grey.

Make Your Own Saddlebag Running Lights.

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saddlebag lights
Buy some marker lights at any truck stop or auto parts store. Run wires from the tail light down to the rear fender.

saddlebag lights saddlebag lights
At the rear fender, mount BMW style quick-disconnects. Wires run from plugs into the saddlebags, then to the lights. Idea and photos by Ron Steiger.

Wiring up extra tail / brake lights

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The Honda Spoiler / Brake Light and the GIVI brake light come with no wiring harness and no instructions. Also, if you want to add something like HyperLights, you need to know what wires to use. So, here's some help.

Warning: GIVI trunks have little spring loaded contacts between the top box and the carrier. If you use your GIVIlight as a tail light, you'll burn out these contacts. You will need to replace them with some kind of connector, like a 2-pin trailer connector. GIVI will not warranty these contacts.

taillight circuit The Honda Spoiler and GIVI trunk come with brake lights only. If you'd like these lights to be on with the tail lights, then brighten up with the brake lights, here's what you do. Where you tap into the brake light wire, attach a diode in line with your connection wire. A diode is an electrical one-way valve, it only lets current go one direction and blocks current from going the other direction. The silver band on one side of the diode case tells you the direction. Current can come out the silver band side, but it cannot come back in that side. So, when you connect the diode to the brake light wires, the silver band should electrically point towards the top box lights.

diode Similarly, connect up a diode to the tail light wire, electrically pointing towards the top box light. Finally, attach a resistor to the diode coming off the taillight wire. Connect the silver band end of the brake light diode to the free end of the tail light resistor. Now run a wire from this junction to your top box light, and another wire from the ground wire to the top box light. Now current can flow through the tail light diode and the resistor to the top box light, or current can flow through the brake light diode to the top box light, but the two diodes stop the current from moving from the tail light wire into the brake light wire or vice-versa. You will have to know if your top box lights are normal automotive bulbs or LEDs.For bulbs, use 10 ohm 10 watt resistors. For LEDs, use 330 ohm 1/2 watt resistors.

resistor If the top box light is too bright on tail light power only, place another resistor in line with the first one, so that the current runs through first one resistor then the second. This cuts the light in half. It's unlikely you'll need more than two resistors.



TailBrights TailBrights
TailBrights - black in daylight, highly reflective at night. $36 delivered.

Turn Signals

Turn Signal Canceler Turn Signal Canceler
Kisan SM-3 Turn Signal Canceler, $100. Replaces plug-in flasher. Allows you to choose using rear turn signals also as running lights.

Make Your Own LED blinkers in your mirrors.

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mirror blinker These are especially suitable for riders over about 6'2" who have trouble seeing the turn signal indicators on the dash.

Idea by Ralf and Elliot, pictures by Ralf.
Buy a couple LEDs at Radio Shack, part number 276-011. About $5. LED
Knock the plastic covers off your mirrors. To do this, stand by your handlebars, and hit the painted covers with your palm on the outer edge. They'll pop right off.

Now, remove the covers entirely from the bike - unclip the two electrical connectors, and take off the tie-wrap that holds the cover onto the bike.
mirror dissasembled
Open up one of the trim holes in the mirror. You can drill it open with a 1/4" drill, or burn it open with your soldering iron. Just be sure to open it up enough that the LED slips in. mirror with hole
Glue the LED into the hole with 90 second epoxy or silicon seal or RTV. LED mounted in mirror
Cut the two wires to the turn signal. Solder in the LED. The LED's yellow wire goes to ground, which is always the green wire on a Honda. The LED's red wire goes to power, which is the light blue wire on the left side, and the orange wire on the right side. Wrap up the soldered joints carefully with electrical tape or heat-shrink tubing (available at Radio Shack). LED wiring
Elliot put three LEDs in each mirror to make turn signal indicators. You can put in as many as you can fit. The power drain is completely negligible. Just keep connecting them up the same way. LEDs in mirror

Plug the wires back in, reattach the tie wrap, and put the mirror cover back on the bike. To do this, line up the three snap-in legs, and give the cover a solid whack with your palm pushing it into the bike.