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Please Help! Need 12v and LED information!

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Please help. If I have to rebuild the internals of my motorcycle blinkers one more time, I'm gonna lose it. I am looking to replace my blinker assemblies with some type of solid state LED set-up. I can take care of the aesthetics, but I need help with the internals. Also, I have not purchased any parts yet, so I am a clean slate.
What I am hoping to make is 2 or 3 rows of 8 yellow(or amber if they make them), 5mm LEDs that can be run off of a 12v DC system. Can anyone make a schematic to show this so I can build them?
Even better, can anyone show the same as above, but having half the LEDs solid on and half designated for the blinker?
The last problem I have is that my flasher relay operates off of the load it normally sees off of the original 1157 type bulb. I think what I want to make is a "load ballancer" or a "load equalizer" to up the resistance the flasher relay sees at each blinker. Can anyone make a diagram for that one?
Again, I would be very grateful for any help you could give. I've been wanting to do this for a long time.



a) Is the flasher unit of the 2-wire or 3-wire type?
b) Do you have a wiring diagram of your bike? If so, can you post it?
c) Are the bulbs normally connected to ground with the positive switched, or to positive with the ground switched?
d) What power rating are your bulbs? 15W?


If you just want to replace the bulbs with LEDs, wire the LEDs as shown in the pic.

You are right, most flasher units are of the bimetallic strip type, which require a load to operate. The resistor is to make up the rest of the load for the flasher unit.


Re: Questions

a)The fronts are the ones I wanted to make 1/2 solid marker light and 1/2 flashing. They are the 3 wire type. The rear are all flashing. They are each 2 wire.
b)I have to try to find my repair manual with the diagrams. If you have a specific question in the meantime, I have a complete wiring harness in my Box-O-Parts and can take a look.
c)I'm pretty sure the ground is switched.
d)I believe the bulbs are 15w(two filament front, single filament rear)

I will try to confirm everything for you as soon as possible. My brain is still fuzzy from the winter. I could have told you all of this in one second last fall before I put the bike away. Thanks again.


You have a flasher unit for each light?? Most cars/bikes only have one for the whole vehicle! Maybe some confusion - when I say flasher unit, I mean the bimetallic strip in a can, not the lights.

Incidentally, what model is your bike? (coming from a bike fan - I rode a CB250N, 1980 model, until it blew up! - Now looking for a VX800)
It's like you said with the single flasher unit. I was wording thing badly. I'm hoping to get the front signals to act like the two filament bulb they are replacing by having half of them stay on as the marker light and the other half act as the signal. The current front blinkers each have a common poitive with two grounds coming out. One for the marker light and one for the blinker.
The rears are a simple two wire, blinker only set up.

The bike is a '93-'95 ZX-7 that I built from scratch a few years ago. I collected parts for a couple of years. When I found a part, I would bring it home and put it on hand tight. When I had almost a complete motorcycle in my kitchen, I decided it was time to start building. By the way, my apartment was on the second floor so eveything had to came apart again go to the garage. I fabricated whatever I couldn't find or didn't like. Nobody was using LEDs when I built it. I thought I was pretty smart at the time by using an LED heat shrinked to a stiff wire as light for my instrument cluster. I was going to race it, but when I was done, I put so much work into it that I couldn't bear turning it into a ratty track bike. :)
Easily Distracted said:
The current front blinkers each have a common poitive with two grounds coming out. One for the marker light and one for the blinker.
Correction. It's actually a common ground with two pos. wires coming out.
I'm going to use a solid state flasher relay so exact load is not as critical. I was just trying to get it as close to the original units as possible.

Also, How hot will a resistor get? can one be layed half in resin without frying anything or next to fiberglass without melting anything?
If you're going to replace the relays with solid-state ones, screw the load, it won't care =).

If you choose to do that, you won't need a resistor at all. First of all, find the LEDs you want to use. I'd say go for at least 8cd. They'll have a voltage drop, usually between 2 and 3.6V. Lets just say its 2V, to keep it simple. If you put 6 of these in series, the voltage drop will be 12V, thus they'll only draw the current they want, almost like they were resistive loads. (If you hook a 2V LED to a 2V lead-acid cell, instead of shorting, it will just draw the 30mA or whatever). So wire them up in for sections of 6 LEDs (but arrange them in 3 rows of 8 ) and you won't be wasting any power at all, and you won't need to worry about hot resistors. If you want some of them always on, just wire them up to whatever controls the front/rear lights I suppose.
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