Ducati Monster Forum

Not sure if I should start a new thread for this, but here goes:

I'm not quite happy with the LED tail light I have on my 695, it's not quite as bright as it should be IMO. I had done an LED light for my bicycle a while ago, with parts from LED Supply (http://ledsupply.com/), so I thought this may be a way to go.

My plan is to use four 3-up Endorstar (http://www.ledsupply.com/endorstar-3up.php) emitters, two with amber LEDs (turn signal), and two with red-orange LEDs (tail/brake light - 2x for redundancy). The emitters will have Carclo elliptical beam optics (http://www.ledsupply.com/10510.php), with the intention of spreading the light more in a horizontal pattern than vertical. I tried these on my bicycle headlight with a white triple emitter (Indus Star with Cree XP-G cool white LEDs (http://www.ledsupply.com/creexpg-w417.php)) and it worked well. The elliptical pattern helped cast a wide beam on the ground without excessive glare for oncoming traffic.

The LEDs will be driven by Buck-puck (http://www.ledsupply.com/03023-d-e-700.php) constant current drivers set up for 700 mA current. This is right up on the edge of what the Luxeon Rebel LEDs will tolerate, but I figured that they will be used at full brightness only for a short time, so it won't impact the lifetime of the LEDs too much. Also, I can dial back the current with the dimming control on the Buck-puck.

As for packaging, at first I thought I could use the existing plastic housing and lens. However, the lens has a diffuser which will interfere with the beam pattern of the Carclo optics. Plus, the Luxeon LEDs generate a lot of heat, and will die a quick death if not properly heat-sinked. I had used LED Supply's 9-watt aluminum housing (http://www.ledsupply.com/alk-lh-9w.php) for my bicycle light, with some minor modifications to add a clamp to mount to the handlebar. They're nice, but a bit bulky, so I'm going with ones from this rather odd site (http://www.ledhousings.com/catalog/index.php?cPath=19_21_27&osCsid=pm4j8qs6ojp7rlq32r417jm1d3). They seem like decent quality, and are reasonably priced. They are big enough to house the LED drivers. If only I had a lathe (and knew how to use it!)

So I plan to get a small mounting plate machined out of maybe 6mm aluminum plate to which the four 1.25" LED housings will be screwed in to. Either RTV or gasket compound to keep moisture out of the LED tubes. The back of the plate has two threaded holes for two lengths of M6 all-thread to mount to the tail-light bracket on the bike. The thick plate will act as a heat sink, and also a convenient spot to mount a small length of 3/8" aluminum channel which contains a length of flexible LED strip (http://www.amazon.com/gp/product/B003G9408K) to illuminate the tail light. After all the fab work is done, I wanted to get all the parts painted (or preferably, anodized) black (would red work better?)

My main concern is road legality. These will be bright - possibly brighter than the original lamps used on the 695. I tested the emitters today without the optics, they're painful to look at directly. Has anyone been pulled over because of mods like this? Will the funky cylinders on the back wreck the looks of the bike? I can always fall back to my old tail light assembly. Just throwing this out there to see if anyone had comments or suggestions - thanks!

Edit: also, has anyone done this before? I did search, but may have missed it.

it won't be DOT legal and the enforcement of that varies greatly based on your location.  There are cities in SoCal we avoid due to the enthusiastic enforcement of turn indicator size/location.  Most others won't even look twice at you.

Will the OP's LEDs be more powerful than the vizi-techs? If not I'm sure he could get away with it.

Interesting. I wonder how bad it is here in Colorado. I did try to find as much info as I could about DOT standards for indicator lamps, all the documents I could find were for cars, not motorcycles. I picked some of the specifications based on the DOT standards, although without testing/certification I'm sure they won't be considered legal.

I found a data sheet for the SupaNova, which says it has 350 red LED emitters at 120 millicandela each, 145 degree beam width. Plugging this in to a formula for luminous flux, I got about 185 lumens. Each Endorstar emitter puts out about 800 lumens when driven at full brightness, and I plan to use two for the tail/brake light. This should compensate for the 50 degree beam width offered by the Carclo optics.

keep in mind turn indicators, legally, need to be 9(?) inches apart (center to center) and some amount of square area, 3 sq inches I think.  So there's more than just brightness.

since it can all be so localized, probably best to ask around your area, or even ask the local PD, off the record of course.  Like I said, even out here there are cities that don't give a damn and there are cities where an integrated tail light is just asking for a fix-it.

I can find the DOT standards if you really need them.

Go for it OP. And post pictures and maybe a tutorial when you're done? 800 lumens will be pretty ridiculous when the vizi-tech is pretty ridiculous already.

+1... If the puck gives you the ability to dial down the intensity, then you have an option for bringing the brightness into DOT regulations.

CO doesn't require signals at all (http://www.americanmotorcyclist.com/Rights/State-Laws.aspx?stateid=6 (http://www.americanmotorcyclist.com/Rights/State-Laws.aspx?stateid=6)), so the whole distance to centerline issue wouldn't affect you (unless, perhaps, you leave the state).

Thanks for the inputs, guys!

I may fall short of the 3 sq in area requirement, but for now I'll try it out and see what happens. Will take pix along the way and write up what I've done. As always, comments and suggestions are welcome.

I got some of the parts in over the weekend, and put them together today for a test run. First, here are the parts for one of the four "tubes":

(http://img171.imageshack.us/img171/1824/img20120528112856.jpg)

Along the top are the end cap, the tube, the triple-LED emitter, the heat sink and the front cap. Bottom row is the Buck-puck, and some die-cut thermal tape. I started off with a red-orange LED module (meant for tail/brake light).

(http://img41.imageshack.us/img41/9051/img20120528113551.jpg)
The emitter is installed with thermal tape to the heat sink. I also drilled a hole through the emitter through which the lead wires are taken through. I used a #30 drill bit for this. I haven't done so on this module, but it's a good idea to de-burr the holes as it can chafe the wire insulation otherwise. You can see some IZ_, out of focus optics in the background.

(http://img195.imageshack.us/img195/6942/img20120528114525.jpg)
Solder the wires to the surface-mount pads on the emitter. Refer the buck-puck documentation for the correct wires to use. Mine happened to be white for +, blue for -. You will find a good quality temperature-controlled iron works well here, as the emitter PCB has an aluminum core, and will conduct away the heat easily.

(http://img12.imageshack.us/img12/7016/img20120528114743.jpg)
Test run, without optics installed. Note the power draw from the DC supply is about 6 Watts. Don't run it like this for very long, the emitters get very hot! The buck-puck is well designed, and I found that it has built-in polarity reversal protection (whew!!!). The LEDs may not tolerate reverse voltage, though. You can then install the optics by simply press-fitting them into the three holes on the emitter PCB.

(http://img688.imageshack.us/img688/9910/img20120528115731.jpg)
(http://img198.imageshack.us/img198/4642/img20120528115735.jpg)
These two shots indicate the elliptical beam pattern of the optics. I'm pointing the emitter+optics to the floor from a height of about 5 feet. The second image has the emitter rotated by 90 degrees - note the orientation of the patch on the floor changes. It's not really this "pink" to the eye, it's more orange-red. I think it looks like this because the camera sensor is saturating.

(http://img842.imageshack.us/img842/6468/img20120528124337.jpg)
This is the test-run of an amber LED module. Power draw is again about 6W.

(http://img43.imageshack.us/img43/6536/img20120528135633.jpg)
This is a small transistor circuit I built to adjust the module brightness depending on whether the brake light is enabled or not. You can just about see the schematic in the background. The 390 ohm resistor causes the REF pin on the buck-puck to be pulled to about 3.9V or so (I determined this value experimentally), and the total current drops to about 75 mA (instead of 560 mA). Grounding REF causes the module to return to full brightness. The transistor switches ON when the brake signal is activated, causing the LEDs to run at full brightness. Note that the schematic calls for a 1k resistor - I replaced this with a 1uF capacitor. This has the effect of making the brake light "fade out" as the capacitor discharges. Charging is virtually instantaneous, so the module goes to full brightness the instant the brakes are applied.

Note: on the turn lights, I added a 1.2k resistor between the +5V and REF lines of the buck-puck, since it was too bright otherwise.

(http://img163.imageshack.us/img163/5201/img20120528143302.jpg)
The transistor circuit, wrapped up in heat-shrink tube to keep it from shorting against anything.

(http://img841.imageshack.us/img841/1491/img20120528154633.jpg)
Group-shot of all four modules, running at full brightness.

(http://img17.imageshack.us/img17/14/img20120528133351.jpg)
As a test, I took two of the modules outside to compare them against the existing tail light. It was a nice sunny day, around 2 PM when I took this shot. The turn light was on, brake light off. The tail light "tube" was set up to run as a tail light (brake line disengaged). The two tubes are wedged beneath my tail bag and the seat. As you can see, they are VERY bright compared to the existing tail light, although they are smaller in area. I should do a similar test at night... Also, this was at taken at work, so that's a helium cylinder off to the left :D


Next step is to get the aluminum parts (except for the heat sink onto which the emitters are mounted) anodized, and to have a mounting plate machined.

Ohmic/Bernard did a 2nd generation of the SuperNova. I don't know the specs, but I do own one. At full blast it's really damn bright and he toned it's max settings down after some testing. It also features 3 settings that you select at power on by holding the brake and release after the appropriate flash pattern. Default is 2/Medium and there's one dimmer and one brighter setting.

800 is probably going to be blinding to someone behind. You want bright, but not so much that you're going to get rear-ended by a blinded car. Perhaps a road test or two with a trailing helper to give you notes on the relative brightness.

One other thing the new SuperNova does is fire off a brief flash pattern when you first hit the brakes after an off period which folks have commented is quite attention grabbing, without being obnoxious.

I too own the new SuperNova and it is awesome.  The superbrake funciton really helps and it is very bight.  It was very expensive but it gives me comfort that people behind see me.

Supa Brake owner here as well, love it! You can see the vehicles behind you the moment you touch the brakes, they give you room...some of them :(  I had this one one "soccer mom" that didn't know the meaning of personal space!! I just had to give her some "sign language" for her to realize she was encroaching on my space!!