I noticed on my '01 GS that one of the rear tail light bulbs were out. I took the cover off and decided, instead of just getting new incandescent bulbs, or off the shelf LED bulbs, I'd make my own.
I broke open the dead bulb to use as a wire connector, then took some measurements of the lens housing and screw hole position. I drew it out onto a piece of fiberglass perf board and cut it out on the band saw. The two holes were drilled out and I went to work laying out the LEDs.
I did some quick tests and aimed for about 20mA per LED string when the brakes were on, and about 4-5mA otherwise. This seemed to make for a bright enough running light, and big enough difference between braking and non-braking. I just did a quick and dirty resistor based circuit. I had the perf board and LEDs already, so this entire thing was free except for my time. I also noticed the clear bottom part of the lens, which I assume is to light the license plate. I threw in 4 white LEDs pointing down for that.
The fiberglass board is sandwiched between the plastic lens and the bulb housing. When I first screwed it in, there was a gap between the lens and the rubbery gasket (from the thickness of the board). I used a big drill bit and drilled a couple millimeters of the plastic screw shoulder and that allowed the lens to squish the board and mate with the gasket.
Sorry about the poor pictures, I can try take more if desired!
(https://lh4.googleusercontent.com/-gZGxAWqhA7s/UMuAcqYijHI/AAAAAAAAnOw/PZVk3SiULdM/s800/IMAG0193.jpg)
(https://lh5.googleusercontent.com/-z3SkHpOCHng/UMuAcBKh_MI/AAAAAAAAnOo/rqeY-4igV1M/s800/IMAG0196.jpg)
Let me know if those pictures don't work!
Ed
Cool. Nice work.
I noticed the Illini license plate cover. I graduated from U of I as well. Are you still in the Central IL area?
I'm up in Chicago now. Had my bike down at U of I for my last couple years there though! Where are you at?
I'm in Bloomington/Normal. Grew up in Mahomet and went to U of I for General Engineering.
I noticed the plate immediately lol... I knew we had an Illinois crowd, but didn't realize we had U of I Alums here!
I'm class of 2011, but I didn't get my bike 'til this last spring.
- Bboy
Edit: Bet I could guess your majors just by the type of work you've done to your bikes! lol
Got any pics of it illuminated, normal and brakes on?
Now what would be funky is to spell out STOP in LEDs on the board. :icon_mrgreen:
Quote from: BockinBboy on December 14, 2012, 01:22:53 PM
I noticed the plate immediately lol... I knew we had an Illinois crowd, but didn't realize we had U of I Alums here!
I'm class of 2011, but I didn't get my bike 'til this last spring.
- Bboy
Edit: Bet I could guess your majors just by the type of work you've done to your bikes! lol
I'm sure this thread is a dead give away to my major! :) I'm a class of 2007!
Quote from: ThatOtherGuy on December 14, 2012, 01:42:27 PM
Got any pics of it illuminated, normal and brakes on?
Now what would be funky is to spell out STOP in LEDs on the board. :icon_mrgreen:
I actually thought about something like that! I should easily be able to put in a microcontroller to do the brake light flashing and all sorts of other animations. Maybe a proximity sensor to trigger the brake lights for tailgaters!
Oh, and I'll take some pics of the tails on and off tonight.
Must be ECE. I definitely enjoy fiddling with electronics too. Class of '06 here.
Quote from: bombsquad83 on December 14, 2012, 03:20:43 PM
Must be ECE. I definitely enjoy fiddling with electronics too. Class of '06 here.
Nailed it!
And the pictures!
First two pictures are with the brakes off:
(https://lh5.googleusercontent.com/-dggBQk1tKQA/UMvQpSpQlcI/AAAAAAAAnQI/C-vNvDpbAec/s512/IMAG0200.jpg)
(https://lh4.googleusercontent.com/-lmRb5AXRJQk/UMvQpawHEWI/AAAAAAAAnQI/gxzALHfWiQc/s512/IMAG0201.jpg)
Brakes on:
(https://lh3.googleusercontent.com/-49OjPOKklmk/UMvQpTSKYbI/AAAAAAAAnQI/gSsF41NgjDc/s512/IMAG0202.jpg)
All were done without the engine running, so it should be a bit brighter.
... Probably cant guess mine through any of my posts here like that lol... ANSC(Animal Sciences)/CHEM majors
Now don't forget the pic of yourself when you tried to get the head-on pic of the leds while still holding the brake and camera simultaneously :icon_lol:
- Bboy
That's an awesome idea! By quick and dirty resistor based circuit... I'm guessing that you added a resistor in the running light wire so it comes on very dim and then a bigger/smaller one for the brake light wire?
I've never tried anything with a resistor but I have a soft spot for anything involving lights on my vehicles
I don't remember the values exactly, but I think the running light is a 910 ohm resistor, then when the brakes are hit, it essentially adds a 370 ohm resistor in parallel to the 910, almost tripling the current running through the LEDs. I can sketch out the circuit if you're interested. Its very easy to make I'd you wanted to give it a shot.
I'm extremely interested in trying it out, but I'm not going to ask you to draw up anything until I have the time and funds to start the project!
Nice work. Through up some schematics with values and dimensions if you can.
Below is the template I used to trace out the PCB, and a rough schematic of the circuit. I arranged it so that it roughly resembles the actual physical layout.
I *think* those were the actual resistor values I used. It wasn't optimal, but it was what I had laying around. With those values:
12V:
Running Lights: (12-(5*2.0))/910 = 2.2mA
Braking: (12-(5*2.0))/136 = 14.7mA
14.4V:
Running Lights: (14.4-(5*2.0))/910 = 4.8mA
Braking: (14.4-(5*2.0))/136 = 32.3mA
I probably should have went with a slightly higher resistance than the 160 Ohm since the LEDs are rated to 20mA, but I'm not really braking for a long period of time, so it should be ok.
(https://lh6.googleusercontent.com/-KQXMvP2hz7g/UNyj05ZmTFI/AAAAAAAAnS8/nEALuwdkd-M/s912/schematic.gif)
(https://lh4.googleusercontent.com/-xnsBiXy9krk/UNyj0-rUxrI/AAAAAAAAnS8/Hi_KUjIB3dU/s1234/tail.jpg)
Looks familiar. I did this the easy way almost 2 years ago. There's a post floating round here somewhere!