Making rear light using LED's

[neatbik]

Hi, im considering making a rear stop/tail light, and i need a bit of info concerning LED's.
I know not very much at all about electronics, all i know is i want a very small light in a custom housing and i think this is the best way to go about it.
I understand you can buy LED's quite cheaply, so can anyone help me out with a 'how to'?
Cheers

[NiteMare]

pop into Maplins

buy as many red leds as you require (you can get ultrabrights) they'll tell you what resistors you need and which leg of the led to solder them to ...

do one set of leds for your tail light and another for your brakelight

i used leds for my idiot lights, sidelights and numberplate illumination
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it ain't broke...

i ain't fixed it enough

[G]

Do not use the same LEDs with the same resistors for brake and tail lights. This does not produce a good enough difference between the tail light and braking.
You'll need to use brighter LEDs or different resistors so the brake lights are significantly brighter.

[SoND]

You've just reminded me they did something like this in 100% Biker. I'll have to try and find it again.
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Go back to bed - You have no rights - "Streetfighters ~ Mainstream motorcycling's crackwhore sister."

[Ariel Badger]

LEDs have two wires, the long one goes to +, the flange on the LED has a flat on it , the flat is indicating the -. Get the polarity wrong and they will not work.
I think you will need a 470R resistor to stop them blowing
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Bikers make great organ donors, get 115 on your licence today.

[neatbik]

Cheers guys

[NiteMare]

the value of the resistor will affect the brightness (how much by i don't know) i used 420r resistors on my leds ...

if you use (random number) 12 leds for the tail light in two rows of 6 you could use 2 seperate rows of 6 (12 in all) for the brake light ...

i'd say that would suffice to show you are slowing ...

you would really need to determine how many are actually needed yourself ...

if you wanted to be really minimal you could get away with 2 , 1 for tail light and 1 for brake ....

don't expect anyone to see them tho...

i use 2 ultrabrights in my headlamp,1 either side and they light it up pretty well, i can see it reflected off the rear of cars when sat at junctions and it lights my yard up easily as well as my gsxr sidelight does
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it ain't broke...

i ain't fixed it enough

[The Shaggy D.A.]

Or buy one of these and take it apart.

https://f2motorcycles.ltd.uk/f2images/upgrades%20images/ledtaillightwhite.jpg

https://f2motorcycles.ltd.uk/upgrades.html
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[map]

FWIW instead of wiring up your own leds why not just buy ready made bulb fit type. These will already have the correct resistors built in and will actually do the job you want.

Some examples if you click here and here.

HTH
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...and the whirlwind is in the thorn trees, it's hard for thee to kick against the pricks...
Gibbs, what did Duckie look like when he was younger?

[Im-a-Ridah]

Thing is its quite tricky to get the most from the LED's, they have a narrow range of voltage in which they are really bright, but are quite sensitive. Since automotive voltage ranges from 12v to 14v you tend to have to play it safe and get sub-optimal output. Making the actual lights isnt too bad if your just doing basic strips of LED's, but if you want loads of them in a small round shape its more tricky.

Also, make use of this calculator

https://led.linear1.org/led.wiz

[Finglonga]

All my lights on the bike and car except the headlight and main beam are LEDs from https://www.ultraleds.co.uk/. No current drain from them at all can leave sidelights on all night without worry of a flat battery, handy with my other half.
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Andy Sez....
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