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PeanutHead
03-04-2013, 7:08 PM
Since I'm ditching the stock cluster, I'm losing the idiot lights. Yeah I know I don't need them but I want to have them there. This will be the first time I've tried wiring LEDs. Here's the info on them so someone can help me.

Amber= VF-2.4V Max; VR-5V Max; PD-100mW Max; IF-25mA Max; IV-5500mcd Typ
Blue= VF-4.0V Max; VR-5V Max; PD-120mW Max; IF-30mA Max; IV-3500mcd Typ

Blackbetty
03-05-2013, 10:47 AM
Obviously you'll need 12v LEDs to work w the system. 12v LEDs usually come with a resistor soldered right on the + terminal of the bulb.

Anyway, I order all mine from here:

http://www.k-four.net/Product.aspx?pid=68#

Already set up for 12v. Just wire them in.

PeanutHead
03-05-2013, 11:37 AM
After I bought these, I found a "How To" site that said to add resistors. If I did the math correctly, one will need a 390 and the other a 280. Since I've already got the LEDs, is it really that big of a pain in the ass to buy resistors?

ThePete
03-05-2013, 3:02 PM
Depends, I went down to Radio Shack for some and so far so good. Granted I'm using the resistor to turn a single element into a dual element on a regular incandescent bulb and its just a stop gap till my new tail lights come in. Just realize that resistors get hot.

Blackbetty
03-05-2013, 4:54 PM
The resistor on one my 12V LEDs from K-four is a 620 ohms, +./- 5%
(blue/red/brown/gold color codes)

PeanutHead
03-05-2013, 7:35 PM
Well, I went to Radio Shack to get some 12V LEDs. I found some on their website and wanted to pick them up. So I get there and they didn't have any of the ones I wanted. Ended up getting some resistors (but turns out they're the wrong ones). The ones I picked up are 330 Ohms. They should be fine for the red and blue LEDs but will they burn out since the amber ones (turn signal indicators) will flash?

Daedalus
03-05-2013, 8:34 PM
http://ledcalc.com/

punch the numbers into this.
put in 14.4v as supply (when charging)
voltage drop across diode is the "VF"
desired current is "IF"

at 14.4v (charging) amber it works out at a 560 ohm 1/2watt resistor
blue it works out at 390ohm 1/2watt

ThePete
03-05-2013, 10:38 PM
Well, I went to Radio Shack to get some 12V LEDs. I found some on their website and wanted to pick them up. So I get there and they didn't have any of the ones I wanted. Ended up getting some resistors (but turns out they're the wrong ones). The ones I picked up are 330 Ohms. They should be fine for the red and blue LEDs but will they burn out since the amber ones (turn signal indicators) will flash?

Radio Shack is a shit sandwich, if you have the time to wait go with a reputable vendor like Digi-Key or Mouser Electronics. I used to do a bit of work with the EOD team out at Miramar and they'd have to bring in some serious Big Bang Theory types from Cal Tech to measure and record stuff with scratch built equipment and that's who they use as their suppliers. If its good enough for the EOD's geek squad their stuff should be more than good enough for chopper and bike stuff.

PeanutHead
03-06-2013, 5:48 AM
Daedalus- thanks for the info. I had the wrong numbers for the formula.

Pete- I'm looking into those sites now. Since I'm using the stock tank for now, I can wait a little bit. Thanks.