led/diode turn signals research

Heathen

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May 3, 2008
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Hi!
i have started to think of making a simple turnsignal system using some simple diode/led's but i'm not quite sure of how to get the turn signals to blink at the right frequency. i have very little electrical knowledge when it come to these things and i'm hoping there are someone here that can help.

i have a turn signal relay for a 6v system that is used on an other bike it's 6 volt with 10 watt light bulbs.

the diode/leds i'm gonna use is 6v 1W, so i figure i need a resistor of some sort. i have calculated(hopefully right) that i need a 4 ohm resistor (all i have found this far is a 3.7 ohm)

now the big question... do i need one resistor for each diode or can i use a 7.5-8 ohm resistor for two diodes(one for each side of the bike). if i'm able to use one resistor for two diodes couldn't i just use one resistor for the whole system and place it between the relay and the turn signal switch instead of between the turn signal switch and the diode?

hope this makes sense to someone!
 
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Good Luck. I don't believe that turn signals are required (California) on a motor driven cycles with a top speed of 30 mph or under. I say motor driven cycles under 30 mph because the CA DMV cites federal regulations for motor driven cycles with top speed of 30 mph when it come to safety equipment on motorized bicycles.
 
turn signals are not required by law here in sweden either, but since i drive it all year round, i do a lot of snow/ice driving so i really don't like to have to let go of the handle bar with one hand to use my arm to signal my turns/lane changes.

i have a setup on my bike now that work fine, mounted a small 6v 1.3ah battery and a pair of small motorcycle turnsignal with 6v 1W smd led replacement bulbs( they are equal to a 10W halogen bulb). and since i added a battery i also stole the reflector out of a 1W led flashlight(bright as ****) and put that into my old 1930's headlight(perfect fit). for the rear light i'm gonna use a 6 v 0.3 W replacement bulb (equal to 3W halogen bulb). all hooked up to the engines light coil so that it will charge the battery a little.
headlight/rearlight will draw 1.5W that leaves about 1.5 watt for charging, the turn signals will draw additional 2W when used and that is more the the engine can charge the battery so i might have to use a batterycharger once in a while but not to often. i'm not quite done yet, missing the bulb for the rear light.

once i'm done and i see that it works properly, i'm gonna take some pictures and write down exactly what components i have used if other people are interested in building a similar system.
 
Even though turn signals, tail and brake lights aren't required on motorized bicycles in most places, I still have them anyways. Along with mirrors, speedometer, horn and head light. I have these for my protection.
 
I think your main trouble with your circuit is that the 6V supply coming off the magneto is not a regulated power supply. It may put out adequate Volts and current while cruising but may be lacking at idle when you would most likely be using your signals, and of course the simplest circuit you would need is a timed RC circuit which discharges through the LED. Of course the timing would always vary if the power source is not regulated making it flash at different intervals. You might try regulating the 6V supply and building a simple timer circuit using a 555 timer chip. Wire it all up inside a tiny box and fill it full of epoxy.
 
A DPDT relay, a cap, and a resistor can be wired to act as a flasher. Ref this thread from about two years ago for further info. Of course, they were using 12 volts, but the circuit would remain the same - you would just use a 6 volt relay, and adjust the resistor/capacitor values accordingly.
 
Diode turn signals

I ballast three diodes on one resistor per turn signal- twelve yellow diodes in all with four resistors. What I have found to work is a green blinker resistor in series on the power to the selector switch... the resistors on the turn signals ballast it well enough... it will 'blink' the line same as Xmas lights on one blinker. You will need to run a supressor sparkplug or the magneto will screw up the blinker signal to a series of random events. I run the blinker right at the switch in a way as to make it visible- then it not only 'blinks' the lines, but also reminds you that the turn signal is running. I have four rigs running this way and they perform flawlessly.
 
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