LED Tailight

[rthughes]

Hey guys.  I decided to make an LED tailight for my bike, and I looked at the previously designed tailight that many of you have gotten and copied it and added an extra circuit so that when you press on the brakes an extra set of lights light up.  I'll get some pictures up tomorrow, but they look just like the previous ones normally and then when you step on the brakes a set of lights in the center light up.

[rthughes]

Normal operation
http://www-personal.engin.umich.edu/~rthughes/GS500E/led1.jpg
During Braking
http://www-personal.engin.umich.edu/~rthughes/GS500E/led2.jpg

[glenn9171]

Nice.

By the way, your speedometer bulb is out and you are in dire need of a fenderectomy. :mrgreen:

[TheGoodGuy]

nice..

your using bigger LED's than what jeffd uses.. am i right?

[rthughes]

yes I do need a fenderectomy, and I am using 12,000 mca LED's.  I found them on ebay for a pretty good deal, I think I paid like 12 bucks for 50.

[rthughes]

Oh yeah and yes the speedo bulb is out, I guess I have to replace it.

[snapper]

I was actually thinking off addinig that to my LED that I got.   :mrgreen:   Haven't done it yet.
Looks good!

[pantablo]

looks good ( I have JeffD's and love it though).

One suggestion-I realize this is prototype but you should be more careful about the layout of the LED's-yours don't look like they are set in a perfect circle and have a definite 'home-made' quality to them. You could polish the overall look up tremendously by this.

[JasonB]

Yep looks like a prototype but hey thats what it is. If you want to test them on another bike I am somewhat local and wouldnt mind a set now that I almost got rearended the other day...lots of screeching and a car going off the side of the road behind. Dumbass shoulda been paying attention!  :nana:

[rthughes]

Yeah I know they aren't in a perfect circle or anything.  Definately a prototype.  I just wanted to get them in there and see what they would look like.  I'll probably polish it up a bit, but I don't think I'll be making any more.

[The Buddha]

Where did you get them...and what is their voltage. I want to make a house number board and would be nice to have it powered by a old bike battery that isn't fit for a bike anymore. God knows I have a few of those lying about...
Cool.
Srinath.

[zoltan]

did you use white leds or red leds? in other words, is the lens cover enough to make a really bright (12,000mcd  ) led look red?

[JeffD]

Now If this is your first time Messing with leds then leme tell you something.   red is a very ineffiecient color for LED's so All I could find were 12,000mcd red with a Viewing angle of 8degrees (very narrow) and for like $0.5 apiece.  The ones That I am using on mine are 4,000mcd and a 20degree viewing angle for ~ $0.4.   Good job too!

And it appears to me that they are red because of the reflection off the lens onto the fender.

One question though.  how are you lighting up the license plate?

[The Buddha]

Where did you buy them guys and what voltage...are they like 12V's that you drop 12 across each or you drop 12V across 2 led's or what...and yea I am planning to get like clear or white or yellow.
Cool.
Srinath.

[rthughes]

The led's I used are some I found on ebay that are 12,000mcd red that have a very small viewing angle, I think something like 8 degrees that was mentioned before.  I got them off of ebay at 50 leds for 12 bucks.  The information I got with them says that you could use them with a 2 volt drop for each led without running any resistors to control current.  So since the average charging voltage is something like 14 v I have 6 circuits of 7 leds each.  So if you wanted to run them just off of a battery you would have 6 leds in series and they should be fine.

[rthughes]

Oh, I don't have anything on there yet to light up the license plate.  I might add a couple more white leds to shine down on the plate but I am not sure yet.

[JeffD]

DO NOT RUN THEM WITHOUT A RESISTOR!!!  You are praying that nothing bad happens to them.  w/o a resistor you are asking for trouble.  Trust me I've tried and got screamed at by the engineers I work with.   Basically if you dont have a resistor you are hoping that each LED will work like its supposed to, but if something happens they all will burn up one after the other.   So if you can take your circuits down to 6 LED's and drop in a small resistor just to be safe.

[rthughes]

Yeah I know about the resistors, you use them to keep the current at acceptible levels so it doesn't blow up your leds, but this is just me having a little fun.  If they go it's not that much of a loss.

[Lex143ms]

You need some tassles for those flagpole turn signals on the back  Nice prototype though.