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Discussion Starter #1
In another thread, debugging a tach, a side conversation started talking about replacing the various bulbs with LED's for the power savings.

Looking up the specs on the stock gauge bulbs.. 160 millicandles bright, 250 milliamp ( 1/4 amp ) current, ~60 ohms filament resistance, at 14V ( not 12 ). Reference number 92069 Part number 92069-1007. Service manual notes it at 12v.

92069-1007 KAWASAKI - incandescent-miniature lamp light bulb lamp - donsbulbs - light bulbs lamps valve valves tube tubes

Looking up a nice cheap spec order LED...

Kingbright - WP7113QBC/D - Round 2200mcd 468nm 30mA Clear Lens 5mm T1-3/4 Blue Thru-Hole LED - Allied Electronics

2.2 candles at 30 milliamps. 8 times less current for 12 times more brightness. ( don't look at the dash, it will blind you ).

12 volts / 0.025 ( 25 milliamps ) yields 480 ohms for resistance in series. Voltage squared ( 144 ) divided by Resistance is power consumption... 144/480 = 0.3 watts so... 10 times less power consumed for about 10 times more light.

RCD Components - CF50S-471-JTW - Axial Tol 5% Pwr-Rtg 0.5 W Res 470 Ohms Carbon Film Resistor - Allied Electronics

470 ohm 1/2 watt resistor, min order 10 at 4 cents apiece... circuit would draw about 25 milliamps at 12v which should light up that LED just fine. At 14v, it would draw 29 milliamps which is still under spec for the 30 milliamp rated LED.


If this preliminary design looks funky/flawed in any way, feel free to jump in and scream.
 

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FREEBIRDS MC CENTRAL NY
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AHHHHHHHHHHHHHHHHHHHHHHHH.Its all Greek to me.
;)
 

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Electronics made easy for Doc

AHHHHHHHHHHHHHHHHHHHHHHHH.Its all Greek to me.
;)

Consider "electrons" to be drops of beer. Voltage is how much beer pressure is in the keg. The reason it's called "volts" instead of "buds" is because the first guy that ever started trying to measure "electric pressure" had a last name of "Volta". For the bike to operate correctly, we try to make sure our keg always has at least 12 cans of beer ready to squirt out the tap, and i do mean continuously.

As the beer flows from the tap, we split it off into various channels to do various things. In that respect, much of the wiring harness is just like the bartender pouring out a mug of beer and sliding it down the bar to each of the "customers" until we shut down the engine and turn off the key.

One particular customer is for example, a dash-bulb. When it turns on, it is getting drunk. Like all customers, the dash-bulb sucks down beer to get lit. That's probably why people get lit the same way, but that's another story. After sucking down a beer, eventually, the bulb has to piss it out. One wire sucks in the beer, the other pisses it out. As long as the bulb is drinking beers, it will stay lit, as soon as the bar closes, the light passes out. The rate at which the bulb can drink and piss is important so that it gets lit correctly. If it drinks too many beers without pissing it will blow up. Fortunately, it's impossible to piss without drinking so it's only important to measure how many beers per second the bulb requires to stay lit. Beer flow into the bulb and piss flowing out the bulb is always constant while it's getting lit, and the rate of flow of beer is measured in Amps. We call the flow of beer current, just like current in a river of beer. A milliamp is 1/1000th of an amp, so 1 amp = 1000 milliamps. 1/4 of an amp is .25 amps which you can just add a zero on the end to .250 amps to see how easy it is to convert to 250 milliamps. If one milliamp were the same as one mug of beer, the stock bulb is chugging 250 beers per second just to stay lit.

Candles for bulbs are how drunk the bulb can get, regardless of how many beers it drinks or how fast it drinks them. The stock bulb can only get "so drunk" before it simply saturates. The effect is sort of like drinking 3.2% beer all day long and only getting a headache instead of even a slight buzz. The drunkest the stock bulb can get is 0.16 candles which is the same as 160 milli-candles. So that's sort of like saying that even though the bartender is sliding 250 beers per second down the bar, the best this bulb is going to do is feel the effects of 1.6% beer, but the keg feels the loss of pressure just the same and the rest of the bar customers are just as ornery about it as usual because most of them are exactly the same as that bulb.

Finally, there is also a little friction on the bar itself. This makes sure that regardless of how fast the bartender could slide mugs along the rail, the table-top of the bar is waxed in a way that keeps them only going "so fast". This is called Resistance, and it's measured in units of Ohms because.... you guessed it, the last name of the first guy that tried to figure out why the bartender was so slow to slide was "Ohm". The wax on the bar, though, is very important because if the bar is too slick, the bartender will slide more beer down the rail than the bulb can even drink, even if the bulb is only getting lit like 1.6% beer, he won't be able to piss it all out fast enough and will simply blow up. For the stock bulb, though, he was created with wax inside his throat ( internal resistance ) so in effect, the bar itself, stock, is just a wire... the slickest bar there can be. As the bartender slides the mugs down the rail, they simply form a line of glasses up to the bartenders wrist but the bartender keeps the pressure on that line of at least 250 glasses per second.

Now... the LED ( light emitting diode ) is sort of like a young 20 something female in a plastic dress that walks into the bar. Our job as bar managers is to kick the old bulb off his stool and give the lady a seat. Before we can do that though, we want to make sure the rest of the bar is happy, especially the keg. We are sure that if we can correctly arrange her seating, she is going to get plenty drunk and that's going to make the whole bar a lot happier. According to what we've heard about her, when she drinks our normal swill from the keg, its the same as getting drunk upwards of 22% beer. ( woot! ) The other sweet thing about her is that to get the 22% drunk effect, she only needs 30 beers per second instead of the 250 the bulb guy was drinking. The problem though, with her, is that because she is a young female, her throat has yet to be well seasoned like an old bulb guy. If she drinks MORE than 30 beers per second, she's upchuck right there and then all over the bar, her head will slam into the rail, she'll pass out and never wake up again. So, obviously, we want to avoid that situation.

We can't change the keg, we want the pressure on that keg to always be the same. We can't change the bar itself, but we CAN change the wax on top of the bar. We will rough it up a little bit using Mr. Ohm's measuring tools so that regardless of how fast the bartender tries to sling mugs down the rail to the lady, the fast as will ever be able to slide will be a maximum of 30 beers per second. After reading the little rules on side of the wax can, we want to apply about 480 layers of wax. So that is the approximate situation we want. Also, as the mugs slide over the top of the wax, they will heat up the bar from the extra friction. Too much heat will cause the bar to burn down and impossible to send the lady any more beer. The "finish" of the wax needs to be such that it can resist the extra heat. We read the side of the can again and that level turns out to be about 300 milliwatts ( or about 1/3rd of a watt ). This is actually great news because the old bulb that was drinking here before was belching up 10 times that much heat into the room just from getting a 1.6% beer buzz. So this is going to make all of the other customers happier since instead of an A/C, this bar only has a fan that turns on when the bartender starts to sweat too much.

The entire point of the entire replacement should be obvious. There are at LEAST a dozen of these old hot bulbs hogging up all of the stools heating up the bar belching, tiring out the bartenders arm drinking 250 beers per second each and they are only getting half a headache instead of getting seriously lit. Does it make sense why i'd want to fill the bar up with plastic ladies for under $10 price tag? I thought so. :)

:nerd:
 
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FREEBIRDS MC CENTRAL NY
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Damn man that was the best description of how electricity works.I have worked in many bars and am a drinker so I understand it well
 
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Damn man that was the best description of how electricity works.I have worked in many bars and am a drinker so I understand it well
I already ordered 25 LED's and 50 resistors. Total cost was about 7 bucks plus shipping.
 

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i have never regretted switching to leds. my cost was more because i dont have the patience to build them and i know it put money in KC's pocket when i bout his. everything but my cluster lights and headlight is led and im searching to change them as well
 

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Several years back I switched my turn signals to LED units. I also switched out the stock brake light bulbs for LEDs and added an LED license plate that has both additional brake lights as well as turn signals. The front and rear stock turn signal units now put out a bright constant running light effect as well as the rear ones also acting as additional brake lights over and above their natural function as just turn signals. The license plate holder has two of the four rows of LEDs acting as additional running lights when its not also used for two rows of brake lights and/or turn signals. Bottom line: the bike is much more lit up. Now, admittedly, I wasn't really caring too much about the specific beer flow these changes brought about but was more interested in improving my ability to be seen by the other idiots on the road. I was aware that the beer flow would be reduced though and that did play a part of my decision to make the changes but simply being brighter was the main desire. The end result was better than I had hoped for and is a no-brainer, easy to do modification for all to do. That being said, while I absolutely LOVE the beer explanation of electricity, I find myself in an odd position regarding this wonderful explanation. My life-long position has always been to have MORE beer rather than less! But in this specific context, less is better. So, RoadHopper, that's a darn good teaching method for getting the points across!
 
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I need a pair of custom shaped LED boards for my rear turn/running lights. Sort of a flat sided cateye. Was thinking about just soldering leads onto a bulb. The bulb in there now is a really small, dual filament and only lights up the end of the lens.
 

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Discussion Starter #9
speaking of beer signals

Lydia ( my ride ) is an '87. The chrome tops of her beer signals have been pitted exposing the plastic underneath the chrome-like finish. Now i realize that everyone else already knows what i am about to say, but just in case . . .

A friend of mine was looking at them today while we were standing around the bike yapping about 20 year old chicks in plastic dresses and mentioned, "Well, they are identical parts, just swap the left with the right". I said, "huh"? Then he said, "yeah so that tops will be on the bottom", and the tiny 3 watt bulb in my brain lit up, but only momentarily ( lack of beer pressure ).
 

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I need a pair of custom shaped LED boards for my rear turn/running lights. Sort of a flat sided cateye. Was thinking about just soldering leads onto a bulb. The bulb in there now is a really small, dual filament and only lights up the end of the lens.
Can you draw it? upload a graphic or a photo of a drawing?
 

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A pic of the lights, those are the el cheapo tail light bulbs too, look pretty cold compared to the signals.:

 

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Discussion Starter #12 (Edited)
A pic of the lights, those are the el cheapo tail light bulbs too, look pretty cold compared to the signals.:

ok, so let me get this straight, please. . . The idea is to have more than one LED spread across the entire turn-lamp, and you want it to curve with the inside of the lens.

Without getting fancy about it, i'd consider 3 LED's. The stock circuit is setup for a quarter amp. 3 LED's would still only draw 1/10th of an amp ( a little less ). They would wire up in a parallel circuit like...

( ignore the commas, the editor deletes the spaces between the wires in this schematic )

------------------------------------------- +
| , , , , , , , , | , , , , , , , , , ,,|
>, , , , , , , , >, , , , , , , , , ,> 470 ohm
<, , , , , , , , <, , , , , , , , , ,<
| , , , , , , , , | , , , , , , , , , ,,|
| , , , , , , , , | , , , , , , , , , ,,|
V, , , , , , , ,V, , , , , , , , , ,V L.E.D.
| , , , , , , , , | , , , , , , , , , ,,|
------------------------------------------- -


( the resistor is based on the part i mentioned in the OP, and if you pick another LED, it's basically a matter of regulating the current down each leg to match the spec of whatever LED you like )

As far as mounting them, seriously? I'd make a mock up first using stiff waxed cardboard tube from the center of a roll of take your pick: meat-paper, aluminum foil, whatever. Get a 12V lantern battery to do it at your desk and spread them until you are getting the desired effect from your lenses.

As far as wiring, solder the resistor and one leg of the LED for a nice thick lead. poke the LED through a hole in the cardboard, tape off some shiny side up aluminum foil to the front where it pokes its head out. TAP into two 18 awg wires and solder the circuit just like it looks on paper in a ladder formation and when its all set, use some glue to cover the back side ( circuit side ) with some more cardboard. Run the two wires through the old lamp's wiring hole and replace whatever is there with a rubber grommet. Basically anything that's stiff is going to work as long as it's non-conductive. The old phenolic circuit boards were invented exactly like i am describing except they would dip them in glue, press and bake them. If push comes to shove, you could firm the assembly up with some metal strips on top and bottom, along the edges, or both.


Now, to get "fancy" about it, you could do more or less the same thing with the addition of a cheap Timer IC to make them light up one by one in series.... like ==> ==> ==> the road work signs do. :)
 

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In your original post, I didn't realize you meant building your own boards instead of using replacement bulbs. That's why I was talking about the flasher when you mentioned the resistors. Didn't realize the LEDs required a resistor inline either.

Thanks for laying that out for me. That's what I'm looking for, light showing across the entire lens vs. just the tip.

So it would look something like this? (just a two minute rough sketch from mspaint)



Sequential lights would be cool, but I probably wouldn't do it since the lights are so small. I looked for any excuse to use the hazard flashers on my 68 Cougar. lol

Is there something else needed to in the circuit to have running lights along with the turn signals?

Thanks again.
 

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plain bare led's will require series resistors, the pre-made led's for auto/bike use (replacement bulbs) will have the series resistors already incorporated within the device.
 

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no need to put a resistor on each LED.
I am not sure why you chose 470OHM resistor, but you can build a series-parallel circuit to run the correct amount of current through the LED's.
this way if one string goes out, you don't lose the whole circuit.
 

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Discussion Starter #16
In your original post, I didn't realize you meant building your own boards instead of using replacement bulbs. That's why I was talking about the flasher when you mentioned the resistors. Didn't realize the LEDs required a resistor inline either.

Thanks for laying that out for me. That's what I'm looking for, light showing across the entire lens vs. just the tip.

So it would look something like this? (just a two minute rough sketch from mspaint)



Sequential lights would be cool, but I probably wouldn't do it since the lights are so small. I looked for any excuse to use the hazard flashers on my 68 Cougar. lol

Is there something else needed to in the circuit to have running lights along with the turn signals?

Thanks again.
Nuuuuuuu

The two wires are your feed and your ground... that's right.

In between those is always going to be 12V ( or close ).

Each LEG of the ladder is setup to be one LED and resistor as a pair. The resistor is what forces the current to be only "so much" and in this case, "so much" is 30 milliamps. Each leg is in parallel to the other legs, like the ladder. But each leg is a circuit of its own right in series. One resistor and one LED in series will feed the LED only the 30 milliamps that the resistor allows down that leg. So just take either lead of the resisitor and one of the leads of the LED set them side by side and use hemostats or alligator clips to hold them still like they are one wire. Then solder them down the little groove they form when layed together into one fat lead.

Single lead _____
Double soldered lead =====
Resistor [00000]
LED -U-

_________[OOOOO]=========-U-___________


Using the soldering iron, melt the casing in a little spot

========== ------- ==========
========== ------- ==========

Thats called TAPPING the wire. No need to cut it. Then wrap one of the leads ( either resistor or LED ) around it like a U. Then solder it. Do the same on the other side.

The advantages of this is that you will have a structurally firm ladder with nice connections.

Notes: Diodes are ONE WAY. They will only light if the correct end is on the positive lead and vice versa. So... regardless of how you hook the resistors up to the LEDs ( with the soldering of the fat lead ). Just make sure you do all three of them the same exact way. You will notice that the LED's leads terminate inside the plastic dress and one of them will be larger than the other. So take your pick which one you want, it makes no difference. Just do them all three the same way. Test with your 9volt battery or lantern battery to figure out which side is positive. Those all hook up to your positive wire. So basically, after soldering all the resistors to their mated LED's, you only need to test one of them to figure out which side is positive... the resistor's open end lead, or the LED's open end lead.

The reason i suggested stiff wax cardboard from inside of a roll of whatever is because you can IRON it. Put a wash cloth over it and use a normal iron, it will flatten out and hold its new shape. After you have your circuit built on the back side, a little Elmer's glue and another piece of cardboard the same side gets pressed onto the back. Iron it, then put a couple books on top of it to keep it pressed for an hour or so. Elmer's sets fast, but it cures over about an hour.

You could use any piece of flat plastic for this as well. Any non-conductive material that's stiff enough to get the job done and thin enough to let you cut it to shape and poke holes will work.

I tried to make this clear but it might still be a bit hazy so if you have any questions, just ask.
 

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So more like,

Positive wire ----resistor----LED-----Negative wire

I like what kc2 mentioned, just need to research what it means. :)
He builds LEDs that dance and dazzle.
 

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Discussion Starter #18
no need to put a resistor on each LED.
I am not sure why you chose 470OHM resistor, but you can build a series-parallel circuit to run the correct amount of current through the LED's.
this way if one string goes out, you don't lose the whole circuit.
The part i found listed in the OP is rated at 30 milliamps for normal output, i.e. to do it right, and not have it burn out. and get the 2.2 candles of output, 30 milliamps is what should be going through it.

The circuit is 14 volts max, 12 volts min. Ohm's law: Volts divided by current equals resistance. Therefore:

At 14 volts: 14 volts / 0.030 amps = 466.66 ohms

So that's a good starting point since we are not using military grade resistors or trying to aim a missile into a keyhole. :)

At 12 volts: 12 volts / 0.030 amps = 400 ohms

For a normally purchased resistor, 470 ohms is common ( insert low cost here ). Common resistors are 5% give or take on their specs anyways. Afterall, all they are is a chunk of carbon baked around some metal leads. It needs to be able to handle the current though, too. So to select the right resistor, we calculate how many watts will be dissipated through 470 ohms at 30 ma.

P = V x V / R ( Power equals Volts squared divided by resistance )

At 14 volts we get 14 x 14 = 196 and 196 / 470 = .417 watts

Half watt resistor would do the trick. That's the worst case scenario. The 470 ohm resistor would mean that the full 30 milliamps would never pass through the LED since 470 is greater than 466, but then again, does the bike actually put out a full 14 volts exactly? Electronics are a lot less magic and a lot more mechanical than most people think. We only want to make sure our LED lasts its lifetime but also want to get close to the mark where it was designed to put out the light.

You could use any resistor you like for whatever LED you select and do your own math though too. ;)
 

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Discussion Starter #19
So more like,

Positive wire ----resistor----LED-----Negative wire

I like what kc2 mentioned, just need to research what it means. :)
He builds LEDs that dance and dazzle.
right. But the easy way is look at the diode. For example, lets just say you like the bigger lead. Trim that lead to the length you want it for your assembly, considering the resistor. Trim one of the resistor leads to the same length. Lay them side by side, put alligator clips on each end near the components ( acts as heat sink for the soldering as well as holding them together ). Heat up the center then feed some solder and you end up with the picture you made above. It will be a single rigid part is the idea.

As far as which side goes to positive, you need to test one of your new resistoLED parts. Put a positive lead from a lantern battery on one end, and the negative on the other end. Did it light up? great, now you know which end is the positive. In series, the current is going to flow through both parts anyway. It doesn't matter which part it goes through first. All the resistor does is regulate the current to spec.


If you are going to use some other kind of LED, then list the specs or do the math to figure out the resistor. The main thing you want to know is what the LED is rated at for current at full output.
 

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all good points, but if we wanted an array of a large number of led's, instead of needing a resistor for each led, you can wire them in series, and even with enough in series, you dont need a limiting resistor. each led has a specified forward voltage drop, and you can use that to calculate how many you need in order to avoid the resistor. if the series string of leds still adds up to less than the supplied voltage, you do then need a resistor, but you need to take into account the amount of voltage needed to drop across the resistor. it will not be the same if its got 3 led's after it, or 5 led's.

you can then take multiple series strings of leds and connect them in parallel to get the desired light output or shape/design your looking for.

thats the way kc's turn signals where built if I recall...
 
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