fitted new headlights

[NickisGod]

Matt wat college did u go to? Honestly i only take a handful of peoples claims and use them as reference. Every time u fire up ur fingers on the keyboard i feel as if ur teaching a class room.

[guns4children]

matt did do a good job at filling us in on how this all works. I skipped all that though and just picked up his "DC kit" comes with everything you need for dc at a low price!

[So Cal Suspension]

matt did do a good job at filling us in on how this all works. I skipped all that though and just picked up his "DC kit" comes with everything you need for dc at a low price!

Ron, STFU about the conversion kit. Seriously, I'm sick of getting PM's about it.

 

 

Nick, I'm not sure if that was a compliment, or sarcasm. Either way I'll respond.

 

I graduated from UCSD with a dual bachelors in Corporate Management, and Cognitive Psychology. I am currently taking classes at the University of Maryland to complete my Masters in Real Estate Development. It'll be a long while before that is done, but it's a goal of mine.

[KAMIKAZE]

just a bit of an update since i havnt been on here for a while

lights a still working perfectly and have a few hours on them now

i just leave them on all the time and havnt seen any issues

[AKheathen]

The LED's used in tail lights are typically <1/2w. Low power LED's generally are fine on AC current since they don't produce any heat.

 

 

Exactly! Thanks for being the guinea pig for us.

 

AC current alternates back and forth. If you imagine a hose filled with water, and it's sloshing back and forth. That's AC current. DC current is water flow in one direction only. LED's by definition are diodes. (Light Emitting Diode). Diodes, by design, only react when electricity flows in a single direction. When LED's are powered with AC current, they are actually flashing. They're flashing fast enough that the human eye can't see it, though. Typically HOUSEHOLD AC current (in the US) is 110vac @ 60hz. That means it's passing by the diode 120 times per second (Back and forth). Naturally, since LED's only "ignite" in a single direction, the lights flash at a rate of 60hz.

 

There is some discrepancy about how many "hertz" the human eye can see, and often times it is quoted in FPS (Frames Per Second) rather than Hz. A common number you will find is 25-35 FPS. That being said, an LED powered by 60hz of AC current flashes twice as fast on average, than the human eye can distinguish. A common rule of thumb is "brightness beats darkness". Meaning, even though the human eye can see ~25 FPS, you will still be able to see a light flashed ONCE for 1/200th(200hz) of a second. Ive heard some people even say you can see a light flash for 1/1000th (1000hz) of a second, and I don't doubt it one bit.

 

Now, being that the Banshee stator fires it's electronic pulses at varying speeds based on RPM; at idle, you are probably seeing 15-20hz of electronic pulses. The Banshee stator has 6 poles on the stator designated to the lighting circuit. These poles make up one half of the stator (We'll call it the right side). The left side of the stator is made up of the ignition circuit. If Yamaha had alternated the poles, ie (ignition, light, ignition, light, ignition, light, etc) the frequency at which the magnet passed over each pole, it would have increased the hz, or frequency electricity is transmitted. Since the lighting circuit is only HALF of the stator, it's got half of a rotation with NOTHING going to it, slowing down the pulses of electricity. The power produced by your stator alternates between ignition, and lighting every rotation.

 

Even after converting to DC current, you will still get pulsing DC current, because of the issues I noted above. This is called "Dirty DC current". The only surefire cure for this is to run some sort of buffer between the stator, and the lights. A battery or capacitor, for example, would store up enough energy to slowly and steadily release power to your lights, and completely eliminate the flicker that you see at idle.

 

 

Hopefully I didn't confuse anyone... I tried to put everything into terms that most people could understand.

 

 

 

 

About your lights blowing up, they'll probably just burn out in a relatively short time. I've powered several of my 3w individual LED's when I was trying to build a tail light without a DC conversion, and they last about 15 minutes of riding. Once the RPMs came up, and stayed up, they overheated and smoked themselves.

 

Hopefully you have much better luck. It'd be pretty cool if those lights work on AC, because I can get them VERY cheap, and can probably keep them in stock for less than $40 per light.

actually, there are a couple corrections i'd like ot point out. first, the stator works on a push-pull paired windings setup. what this means, is that the magnet polarity in the fly wheel is alternating. one magnet pushes the fieldaway from the magnet to the next pole, where that magnet is, at the same time pulling. when it moves one magnet, it does the opposite. that is how it is generating ac. if the stator was wound in alternating circuits, then all poles would be either pushing, or pulling, and not pass across the circuit, other than a transient magneto effect.

one thing about the led failure, is the reverse current and resistance. when the direction changes, there is actually some leakage allowed to pass, and there is also heat and break-down created. this effect is greatly correlated to the purity of the surface media. manufacturers are constantly improving the purification and contamination control in their facilities to improve efficiency, output,(both amount, and coor quality) and durability. that is why led christmas lights are now practical, and why they can even make a high-output led in the first place. so, i suppose it really depends on the led manufacturer, and when they were made. i am actually in the process of designing new led drive ic circuitry to further improve the output and efficiency of led's. i would venture to say, it is plausable that you can now buy lights like that that will not have an issue running ac, but it is not likely to be on the cheaper side.

 

as for advise, i would at least switch the polarity of one light, so that each light takes a different side of the wave. this way, one light will both use, and shunt the power that would otherwise be opposing the other light. it will also free-up a lot more flow from the stator, allowing it to run full-wave, rahter than half-wave, as you are probably running.

[SpecialEd 05]

Just wondering, would wiring in a bridge rectifier work? Especially on Matt's LED lights? Seems like it would be simple to make up with the right components and wire in line before the lights.

 

http://www.allaboutcircuits.com/vol_6/chpt_5/6.html

[So Cal Suspension]

The problem I have come across in my past experimentation with simple bridge rectifiers, is in order to avoid the pulsing that inherently comes from this sloppy AC current, you still must run a capacitor in line to "absorb" the pulses. After rectification, obviously, it would then be DC "pulses".

 

To rectify, and cap a 10w 12v lead to each light... it would be safe to assume that a 12v 15,000uF capacitor would be needed. (Utilizing the general rule of thumb of .0015 F per watt, converts to 1500uF per watt of 12v DC current.)

 

Just for visualization purposes, Philips manufactures a 12v 14,000uF Capacitor that measures roughly 1.4" in diameter, by about 3 1/4" in length, with two screw terminals. It retails for $6.99.

 

 

One of these would be needed per light, in addition to a bridge rectifier capable of an output greater than 860ma @ 12vdc, with a nominal input of 9-36vac. I haven't found anything with a forward voltage of 12vdc+ with such a low AC input. I haven't done a ton of research on this, other than what I've mentioned above, as my lights are intended for DC current, and DC current only. The DC Conversion is such a simple process, that investing in an alternative "bolt on" application would never pay itself back.

 

Let's face it, lol, a lot of people have trouble with the basic DC Conversion, wiring and soldering in bridge rectifiers and capacitors would be like brain surgery.

[SpecialEd 05]

So true, and the loss of end voltage after the rectification would be more with this method. I guess if you want a 'bolt-on' DC power source then something like a 5000mah LiPo battery from an RC car would work. Say for someone that wants a removable add-on LED lighting setup.

 

Something like this would give around 4-5 hours of lighting from 2 of Matt's lights at 14.8 volts.

 

http://www.ebay.com.au/itm/2x-5000mah-HARDCASE-RC-CAR-14-8v-4S-lipo-li-po-battery-1-8-scale-buggy-truggy-/261038128902?pt=AU_Toys_Hobbies_Radio_Controlled_Vehicles&hash=item3cc715bf06

[AKheathen]

seems a bit much just to kill some idle flicker. if you are really worried about the reverse voltage, wire one of these inline: http://www.digikey.c...ND/3451530��pdf data sheet: http://www.diodes.co...45SD1.pdf.��one of these alone can handle the max load of a stock stator with minimal loss, and only $0.90 each. again, i suggest wiring one light out of polarity with the other to get the best performance from the stator.

 

a guy could use 4 of these in a dc conversion, as well.

[AKheathen]

So true, and the loss of end voltage after the rectification would be more with this method. I guess if you want a 'bolt-on' DC power source then something like a 5000mah LiPo battery from an RC car would work. Say for someone that wants a removable add-on LED lighting setup.

 

Something like this would give around 4-5 hours of lighting from 2 of Matt's lights at 14.8 volts.

 

http://www.ebay.com....=item3cc715bf06

lipo batteries are dangerous, and take a special charger for safety reasons. as long as you mount it well with good cooling and don't exceede max recomended drain rate, you could make it work.

[So Cal Suspension]

We've used LiPo batteries on every bike we've built to run lights, and fuel pumps, and have had great success over the last 3 years. We use the cheap "HobbyFans" brand from eBay. Straight from hong kong. No issues to speak of.

 

I've also bought an ungodly amount of these...

 

http://www.ebay.com/itm/Practical-New-AA-12V-1800MAH-Ni-MH-Rechargable-Battery-Pack-3-/290687227550?pt=US_Rechargeable_Batteries&hash=item43ae4f169e

 

One of these batteries ran two of my lights for 90 minutes at full power.

[AKheathen]

what's the highes discharge rate you've put on them? and, what charging method/rate? i'm not sure how much the lipo batteries have changed in 5years or so. i just remember what i learned when they were coming availabe for my rc plane, that, if they do go, they have much more energy than any other common battery. the main fix for this is charge and discharge controllers and internal heat sensor/switch. got a link to your lights? still using those same raw leds, or did you find newer stock?

[So Cal Suspension]

Oh yeah, thosePhilips LED's are old news, I just threw away about 1,000 of them. I'm using 10w Cree XM-L.

 

I believe with the fuel pump and two lights, they're drawing well over 3000mah.

[AKheathen]

man, you could have thrown them this way. they get hot as a sumbish, but work for maglights and such. i just got 12 plcc for testing. gotta find a bunch of useable ones cheap to cook on the test circuits to find some overrun effects

[jbooker82]

 

 

There is some discrepancy about how many "hertz" the human eye can see, and often times it is quoted in FPS (Frames Per Second) rather than Hz. A common number you will find is 25-35 FPS. That being said, an LED powered by 60hz of AC current flashes twice as fast on average, than the human eye can distinguish. A common rule of thumb is "brightness beats darkness". Meaning, even though the human eye can see ~25 FPS, you will still be able to see a light flashed ONCE for 1/200th(200hz) of a second. Ive heard some people even say you can see a light flash for 1/1000th (1000hz) of a second, and I don't doubt it one bit.

 

Solder an led on the end of a ac power cord. Plug it in and swing it around in a circle. You can really see the 60hz affect. The circle is made up of a bunch of dashes.