I honestly can't stand halogen bulbs. They have ugly (IMO) light color, poor lifespan, and not energy efficient. I tried a xenon bulb with a projector housing and although it offers some key advantages over halogen (longer life, better color, less power consumption) I still wanted LED. LED's are even MORE efficient and last longer than xenon. They also have full brightness from the moment power is applied (xenon takes a few seconds to warm up).
From my research I could only find two DOT approved LED headlights for motorcycles. Trucklite and JW Speaker. The trucklite has a terrible beam pattern (blows my mind that it got DOT approved) and JW speaker is $500.
To the drawing board!
I'll make my own LED headlight. My main goal is honestly to have a LEGAL beam pattern.
To make building it easier, with my limited resources, I will be modifying a xenon projector headlight housing instead of designing one from the ground up. A xenon projector housing will be cheap and easy to source. A xenon bulb puts out about 3,000 lumens but at most, only half of this light actually comes out of the lens and is projected onto the road. My idea is to utilize a single, high power, LED in a vertical position. Because of the LED's 125 degree beam angle, the light efficiency will be very high. So 3,000 lumens won't be necessary.
The LED emitter I will be using will be a Cree MK-R
http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Arrays-Directional/XLamp-MKRThe MK-R one of the worlds more efficient LED emitters. It produces a max of 1,700 lumens and has a color temperature of 6500k which is as close as it gets to daylight. 1,700 lumens is more than the stock halogen bulb produces so the MK-R is the perfect choice. Also, the MK-R runs off about 11.7 volts so the constant current driver I will need to run the LED will be working at a very high efficiency because it's power source will be my bike's 12 volt circuit.
Attached is a diagram of a standard xenon projector on left and my modified projector on the right.
So basically I'm retrofitting a xenon retrofit kit. RETRO-CEPTION
The process is fairly straight forward. Add a heat sink to the reflector bowl (of the aftermarket projector) and bolt the LED emitter to it. Be sure to use thermal paste and position the emitter AT THE FOCAL POINT inside the reflector bowl.
I tested it to make sure it was positioned properly and that the heat sink was suffecient to dissipate the heat. The MK-R is incredibly efficient so it doesn't produce much heat.
Look at that perfectly (kind of) positioned emitter:
Don't forget the constant current driver:
To get the projector retrofit kit inside of the stock Zero headlight you will need to remove the polycarbonate cover. A heat gun does the trick of reactivating the sealant allowing you to pull the assembly apart.
Some modifications to the stock headlight reflector dish are needed to fit the retrofitted retrofit projector. (the reflector dish was spray painted black during an early project of mine so that's why it is black in these pictures)
Reinstall the glare shield:
Put the lens back on the retrofit projector and then put that whole assembly back into the stock headlight housing. The yellow ring around the lens is called a COB (chip on board) LED ring. It's insanely bright and crazy efficient. Not only does it look cool but this will be my daytime-running-light as required by Florida state law. The projector headlight has such a sharp cut off that during the day it's hard to even tell whether or not it's on (if viewing from above the cut off point) So the LED ring is a good addition.
The retrofit project was too big to fit so I had to cut a hole into the polycarbonate headlight cover (I cut the hole bigger than needed so the projector can be adjusted up and down when I'm aiming the beam):
Since the clear cover can no longer be returned to its original state anyway, I spray painted the inside of it black to make it look more aesthetically pleasing. Tonight when it gets dark I will aim the beam and then seal around the gap between with two parts with black silicon:
Installed on the bike:
IMO the blacked out cover looks a lot better than seeing the ugly chrome reflector dish.
COB LED ring (told you it was bright):
LED projector turned on (COB LED ring turned off)
COB LED ring from far away:
Beam pattern of LED projector:
Not too bad if you ask me. Pull your Zero up to a big wall and see that the stock halogen bulb/reflector housing produces a mediocre beam pattern. My LED headlight has a sharper cut off and better light distribution. The lines/rings you see in my beam pattern are because of the cheap retrofit reflector bowl. I got the retrofit kit for $20 so I'm honestly not surprised it wasn't a perfect ellipse. Buying a better quality retrofit kit would improve the beam pattern even more.
I think it's safe to say that my idea to use a small LED emitter (pointed upright) inside of an elliptical reflector dish worked pretty well.
I hope this idea will provide you guys with a cheap and effective way of implementing LED technology into your headlights.
