Any other ideas to narrow and focus the beam? The MR16 seems to be wasting light all over the place.

Thanks.

You should use an MR16 spot rather than a flood, which you probably are using now. BTW an MR11 is much less efficient than an MR16.

I'm trying to find an MR16 spot, but my local Home Depot and Lowes don't carry them. I've found it on the internet, but for $12.50 + tax. Ouch. Any ideas?

Try the folks at Harrington lights they sell both 10w and 20w MR16 narrow spots. I bought my lights from them and they arrived quite quickly. Here's a link.

http://www.harringtonlights.com/Glas...hour_lamps.htm

Electronic Goldmine has 12V 20W MR16 spots with cover glass for $1.99...

http://tinyurl.com/7xgtr

Hey, the flashlights finally arrived today, and they are crazy bright! I can illuminate a reflective street sign from 150 feet, and my wife tells me they're blinding from across the street. The focus is a little tighter than I'd prefer, but they should do fine. Now the next step is to resolder the connections (they're terrible!) and wire up a connection to my battery. Hopefully I'll be able to do all this tomorrow, we'll see.

BTW, would anyone happen to know where I can get 1/2" OD semi or fully transparent rigid plastic tubing? I tried Home Depot but that was a bust.

Yes! figuring in feet travelled/sec (and say a 2 sec response time). 150-175' is a reasonable throw distance. Esp if you cycle over 20mph.

I'm amazed at what they can do with a simple lens to amplify light!

Oh, there's no lens in these flashlights, just a reflector (or is that what you meant?)

Anyway, I finished the wiring today, and I'm currently looking for some P-clamps to mount the flashlights to the handlebars. I have some pics, and I'll post them when I figure out how. But first, some observations...

These flashlights were those generic MXDL "Luxeon" flashlights you can find on eBay. I should note that these do NOT use genuine Luxeon emitters, rather they appear to be Chinese knockoffs. Still, they are really bright!

I bought a set of three, and they are all different colours. One has a blue tinge, another pink, and the third is a yellow-white. The last one is the brightest.

About heat: These things get hot! I am running them from a 9V source with a 1.5 ohm resistor, so that each one will get 4V at 700 mA (actually, 660mA). After less than 10 minutes they became uncomfortably hot. They are designed to operate with three AAA batteries which will theoretically force 4.5V into each emitter, though I doubt you'll get 700 mA out of a AAA battery! Luxeon's datasheets go into great detail about heatsinking, and as far as I can see, they need quite a bit. The knockoffs are no different, and I am considering using metal P-clamps and a metal base to screw them onto, for a little more heatsinking. Alternatively, I may replace the 1.5 ohm resistor with a 1.8, so that they don't draw so much current. It's a good thing that the flashlight bodies are aluminum, or they'd have burnt out already...

One other thing, the battery did not heat up at all during this time, so that's good. At least it can handle this current drain!

Argh! Bad news mates. The flashlight headlight system is broken, I suspect a short circuit may be the culprit. I KNEW I should have rechecked that shoddy Chinese soldering. I think one of the emitters may be down, but I can't be sure until I take it apart and test the emitters separately. Well this is rather a waste, but it's better that it died now, rather than in the middle of a night ride!

The saga continues. After reviewing my calculations, and after comparing them to datasheets and actual measurements, it would seem that I screwed up the resistor value. GREAT JOB, JEFF-O! Argh. Too much current was getting to the LEDs and one of them just bit the dust. No wonder they were getting so hot.

So anyway, I'm going to have to order some new LEDs, but I think I'll get them from Future Electronics. They'll cost a pretty penny ($8.50 each), but at least they'll be genuine Luxeon parts and not generic Chinese knockoffs.

*sigh* This is getting expensive, but at least I'll get what I want...


UPDATE: Well, I went ahead and ordered those Luxeons to replace the ones I blew up (still kicking myself over that). I got two red emitters as well to make shipping worthwhile, maybe I'll make them into ground-effect emitters like I saw earlier in this topic. My wife says she'd rather my bike glow red, than to see me in a neon green safety vest. ;)

Sorry to hear about your zapped LEDs. They are rather delicate electrically, but once you've got them set up they should be super reliable.

Ah, don't get me wrong, I know all about the delicacy of super-bright LEDs. I suppose in my haste to complete this project I skipped over some precautionary datasheet double-checking and measurement-taking. By all means I recommend trying the Chinese flashlight knockoff bike light conversion, just don't duplicate my mistakes as well! Unless of course, you WANT the project to cost $20 more and be delayed another week.

Here are some pics I took tonight of the Speedmachine with the lights on. The front turn signals are mounted on the ends of the handlebars and the rears are part of the module on the seatback. They are quite bright — you can see how they light up the garage door.

The front view shows the Nite Hawk Emitter headlight, and in the rear view you can see the 56 LED taillight/brake light. The Warp Drive casts a large pool of light on the ground. When I go out at night I attach a halogen headlight with a separate battery, which isn't in the photos. It's really wild flying down the road at night with all the lights blazing.

Sweet pics, Multibiker! I expect my replacement LEDs to come today (FedEx said so), so I'll begin work on them tonight or tomorrow. The heatsinks the flashlight LEDs are mounted to are quite effective, so much so that I'll need a second hand to help me remove the old lights and solder the new ones. Good thing I work at a tech company with lots of skilled operators (Not that I'm not skilled myself!)

I ordered Luxeon Hex Stars for the red lights, so they are already mounted to a small heat sink PCB. I won't have to solder those, just mount them to a larger heatsink.

Oh man, I can't wait until it's all done! :D

Alright, the old chinese "luxeons" are off, and the new genuine ones are attached. After I'm finished work at 11 today, I'll assemble the rest of the lights.

It's interesting, it says right on the Luxeon datasheets that the heat slug on the bottom of the emitter is not electrically neutral, and should be allowed to connect to either the anode or the cathode of the LED. The chinese knockoff is built almost exatly the same, yet the heatsink it's mounted to in the flashlight connects the slug to BOTH the terminals... perhaps the slug on the chinese version is insulated? It sure looked like bare metal to me. In any case, I cut up a TO220 transistor insulator and put a piece under the new luxeons... just in case. I hope that the thermal transfer isn't affected too much though.

All this info is probably boring you all to death, but nobody I know really cares too much about this project. Ah well, they will when they see it done, and want one of their own! Haha. Anyway, back to work now.

The Chinese LEDs may be insulated but the Luxeons are not, so you are wise to use an insulator between the slug and the heat sink. You might consider smearing some heat sink compound on both sides of the insulator to ensure a good thermal contact. You can get it at Active Electronics, Radio Shack or most other electronics or computer stores. You're right, this stuff bores most people, but geeks love it.

I put heatsink compound on a few of the mechanical connections in the flashlight, like where various places screw together. The body of the flashlight still gets pretty warm though, so I guess there's enough heat being drawn away from the LED. I may end up having to clamp the flashlight to the bike with metal clamps, so that the bike can be used as a giant heatsink. More testing is in order, I think, before I take it on the road.

Awesome lights. What sort of response are you getting out in traffic?

Thank you VR. I've been riding daily for three years now — the Speedmachine since last June, and mountain bikes before that. Confession: I don't commute (I work at home) but I ride an hour and a half every day, 365 days a year, sun, rain, snow, whatever, usually during the evening rush hour because that's the best time for me to get away.

So compared to a pair of Cateye LD600's, I believe the lights have made a big improvement in my safety. Drivers give me more room when they pass, at least half the lane in most cases.

The tail/brake light is inherently more effective than a flashing blinky because it gives drivers more information than just my position. It tells them something about my intentions. When I hit the brake I can see the vehicles in my mirror slowing down. They don't come up as close behind when we're stopped in traffic either.

The turn signals are the best feature, though. They make the whole intersection thing a lot more predictable and drivers seem to appreciate that. I have always used hand signals and the problem I found is that a lot of people don't understand them. If I stick my left hand up to signal a right turn, probably a third of the drivers don't know what it means. I can tell by their hesitation. But they understand a flashing light. And taking the lane to make a left turn seems much more secure now. I can see the drivers around me reacting and backing off because they know what I'm doing. All in all it's more like riding a motorcycle than a bicycle.

Yeah I'm getting similar responses and nods of approval from drivers. Nobody likes second guessing a ped or cyclist. Also drivers seem to better judge my speed.

Which means a safer ride for you. I'm still having problems with drivers judging my speed. When traffic is light I will cruise at 20 - 24 MPH and I've had a few drivers pull out of side streets and driveways while looking right at me and I had to hit the brakes. Jaywalkers are bad too, they can't be bothered to judge the speed of an oncoming bicycle. What we need is a cloaking device that makes us look like a huge dump truck or something.

With some white bedsheets, popsicle sticks, paint and duct tape, I can make that dream a reality my friend!

Ditto. The lights fixed back and side problems...but oncoming is still a problem. I'm traveling at your speeds same thing. Not sure what to do about it. When dealing with questions like this, I usually resort to how I judge things while driving. How do we judge how fast a car is traveling? uh I'm thinking.......

By how fast it gets big? Maybe we don't get big fast enough. I think too that people are conditioned to believe that bicycles move slowly because most bicycles do. I'm going with jeff-o on this one. Now where did I put those popsicle sticks...

Wow those LEDs are cool! I'd consider using little clusters of convention LEDs before superbrights, $8.50 vs. 20 cents or so each...... but with LED technology you can put turn signals on a bike and have them weigh next to nothing, have a turn/brake setup, and yeah, it might get a little more respect from some motorists.... this reminds me of the turn sigs etc my older brother's Stingray came with, back in 1968......