First off, special thanks to Bike Forums for the information and inspiration to conduct this little experiment. Everyone who has written/posted here has been very helpful, and I am grateful. Thank you all.
After reading stuff in this forum (Electronics, Lighting & Gadgets), the Bicycle Lighting Systems website by Steven M. Scharf and other random internet link surfing, I rode last winter on this setup (click on the images for links to their product web pages):
These are the Optronics driving lights I found at some local automotive store. I mounted one of the pair to my front reflector bracket. They use a 12v, 50 watt MR-16 bulb, are small in size and put out a lot of light.
This LED marker light is designed for 12v automotive operation. It is bright when energized, with two large red LEDs on each side and four smaller red LEDs in the center. It is designed to throw most of it's light forward and a little to each side. I mounted this on my rear rack between my pannier boxes facing to the rear. In addition to being bright, it is also reflective.
I have access to these SLA batteries at work. They are replaced regularly and I simply use the old ones that seem to have a bit of life left in them. The set I used last year was 6 volt, 10 amp-hour from an emergency lighting system. I connected two in series for my 12 volts and they fit nicely in my rear pannier boxes: I got four of these boxes from a friend who wanted to get rid of some of the stuff in his garage; I fitted two of them to my rear rack using simple P-straps.
I use this power supply to recharge the batteries. It is designed as an uninterruptible, battery-backed source of power for security systems and such. Kinda expensive but it is designed to properly charge SLA batteries. As I had one laying around, I put it to use.
This was not expensive for me. I already had the boxes, power supply/charger and a supply of SLA batteries. I paid roughly $20 for the driving lights (and only used one of the pair) and $13 for the LED marker light. The wires and various connectors I had laying around.
After mounting the lamp to the front of the bike I simply ran wires from the battery to the two lights without using any switches. I used a quick-disconnect coupler for the headlamp. I would burn both lights (front and rear, that is) when riding to work in the morning but only energize my rear LED marker light in the afternoon as the battery would not have enough capacity left for the whole ride. Once at home I would take the batteries out of my pannier box and put them on the charger, then take the second set of batteries and put them on the bike for the next ride. Each set would have roughly 24 hours to charge, if I remembered to change them at the same time each day...
I liked the amount of light I was able to ride by as much of my route was without street lighting due to construction (thankfully, that is over with.) However, I got comments from co-workers that my lighting was pretty bright. I knew the MR-16 bulbs were not designed for road use and had a conical projection pattern.
I was concerned I was blinding oncoming drivers so I began thinking about alternatives.
I settled on buying these:
This headlamp is designed for motorcycles and its H4 bulb is (roughly) the same wattage as my 12v 50w MR-16. It has a larger reflector, ECE approved high/low beam configuration *and* a 5 watt running lamp. Replacement H4 bulbs are readily available in various wattage configurations, even HID if I so desire.
From the product description and the manufacturer's website this switch should bolt nicely to the 7/8" handlebars of mountain-bikes.
I plan on putting the headlamp, battery, wiring, and any other controls in a waterproof box and mounting it all on my new front rack:
I got mine from Abaxo's Ebay store here.
When the parts arrive I'll make an attempt to dress the wiring neatly and post some pics of the installation. I hope to have figured out a way to use the turn signal and horn switches. I'm thinking about going with systems for scooters & mopeds as they are less expensive than motorcycle gear. The switch assembly includes a 'kill' switch to kill the engine on a motorcycle. As I'm not interested in killing my engine I want to concoct an alternative use for this, such as an intermittent high-beam flash function - should be a good attention getter.
Please let me know what you think about this setup as I'm fishing for feedback. It is not my aim to blind other road users. This headlamp should be street legal lighting and is the same wattage as what cars & motorcycles use. It will be less bright because I'll have no alternator/generator supplying power, only a battery so the system voltage will be less.