Picture
The tail light saga is a long story, so I'll try to spare you the boring details. Long story short I did quite a lot of Google image searching for the perfect tail light for my motorcycle. What I thought I liked was a tail light called the "mini Texas" (shown bottom left in the picture of the 4 tail lights). It was backordered and I waited and waited for it. Its a nice little tail light, but after holding it up to the motorcycle, its not my style - probably better suited for a bobber or similar.

So I went back online and ordered 4 other different tail lights (that would be 5 total, for those of you keeping track). What I finally decided on is an old school Lucas-style tail light. It is a repop made by Emgo with an aluminum housing (similar to this one). Its much smaller than the OEM tail light, yet has some café racer style to it. While I was at it, I also took the time to chop the rear fender. I took roughly 5 inches out of it, and it looks nice.

I re-located my license plate to a bracket that is attached to the lower shock mount. I had planned to make my own, but got lazy and ordered this one. I wound up using a short spacer on the mounting bolt to get the spacing I wanted. At some point I will fab my own version to get rid of the spacer. For the top two license plate bolts, I used LED bolts for illumination. I also added a second brake light (an LED module) on the license plate frame. Its a waterproof unit, and uses VHB adhesive to attach.

After some brake light testing, the hydraulic brake light switch failed and would no longer trigger the lights. I've actually run into this problem before on my VW. Typically the switch contacts get melted/scorched because of the load across them. At the time I was running an incandescent 1157 bulb (8w/23w dual filament) and the LED module. These brake lights have a draw of 1.92A and 72mA respectively, for a total of about 2 Amps when both brake lights are illuminated. The easiest way to solve the problem is to throw an automotive relay in the mix, so that the switch is not seeing the 2 Amp load, but rather just triggering the relay. For all you nerds: a typical Bosch relay coil draws about 160mA (FAR less than the 2A the brake light switch was seeing). For further protection, a flyback diode can also be installed (make sure you orient the cathode correctly). Refer to this reference for a basic wiring diagram, to include the diode (note that the capacitor discussed in this reference is overkill IMO). I installed a new hydraulic brake light switch, and no longer have any issues. Note that I also installed a new mechanical brake light switch for the rear brake.

To take it a step further, I also decided to convert the 1157 incandescent tail light to LED. LED's draw much less power, which is important on a motorcycle. I used this LED bulb in red. Note that with LED's that are put behind colored lenses, you must use the same color LED as the lens color, otherwise strange color filtering effects take place. I was a bit worried the LED bulb wouldn't be as bright, but if anything its actually brighter than the incandescent! The pictures don't do it justice. For comparison, the brake light on an 1157 incandescent draws about 1.92A, but the brake light on the LED bulb draws about 165mA (nearly 12 times less). To add extra visibility, I also added a brake light flasher. This particular one has a bunch of different modes, and works really well. I have included a video of it in action on my bike below.

For you nerds who are thinking "hey, you probably don't need that relay you just installed anymore, since that LED bulb draws much less than the 1157 incandescent bulb" - you are probably correct, BUT it still serves its purpose. Note that the LED 1157 bulb draws 165mA, and the LED module draws 72mA for a total of 237mA which is still greater than the 160mA that the coil of the relay draws (so there!).

While I was in the LED conversion mode, I also swapped the incandescent idiot lights and gage illumination lights with LED's. I tried a bunch of different styles from superbrightleds.com, and finally settled on the best: for the idiot lights, I used 1 each of these LED bulbs (12VDC, 120 deg. beam angle) in yellow, blue, red, and green. For the gage illumination lights, I used these LED bulbs (12VDC, 90 deg. beam angle) in green. Overall this configuration of LED's looks really good, and matches what it looked like with incandescents. Note that the face on my tachometer is very faded, which is why the color bleeds through so much - this will be fixed once I restore the gages. Also note that with LED's that are put behind colored lenses, you must use the same color LED as the lens color, otherwise strange color filtering effects take place.

After doing some night riding, I came to the conclusion that my H4 bulb wasn't cutting it. A potential solution could have been to install a better bulb and run the headlight wiring thru a relay directly from the battery, but I thought I would give an HID kit a try. I used a cheap H4 35W 5000K hi/low kit from DDM tuning (hard to go wrong for <$40). It was shipped directly from China - but appears to be high quality. The kit comes with the bulb, harness, ballast, igniter, and a relay unit for switching the high/low beam (which really only extends/retracts the bulb via a solenoid). I hooked it all up, placed the igniter right behind the headlight bucket, and the ballast went under the headlight bucket attached to where the old brake junction/switch used to go. It actually works rather well. The high/low beam option doesn't make much difference - it slightly shifts the beam up higher, but not by much. Otherwise, it throws out a crap-ton of white light. As an added bonus it draws less power than the old halogen (35W for the HID vs. 55W for the halogen). The only downside is that there is some glare and the cutoff pattern isn't real crisp, which is typical of an HID conversion using an H4 based reflector (the best HID systems use projectors). Glare and strange beam cutoff patterns can cause a problem with oncoming traffic, but can be mitigated with good headlight aiming. If I were doing a lot of night riding, I would probably convert to a projector based system, but for the occasional night run this setup works for me.

Here's some video of the brake lights in various states of ambient light. Note that the camera doesn't do a particularly good job of picking up how fast the lights strobe due to the frame rate:
This is a video of the LED idiot lights and gage illumination. Note that the face on my tachometer is very faded, which is why the color bleeds through so much - this will be fixed once I restore the gages. Also note the HID was not installed yet for this
video:

This is a video of the HID headlight:
T_The_Pirate
2/7/2014 08:33:13 am

awesome brightness!!

Reply
2/8/2014 12:25:00 pm

Thanks! The HID is certainly nice, but you will wind up with some glare. As you will see in the next few updates, I opted to go back to a standard H4.

Reply

Your comment will be posted after it is approved.


Leave a Reply.