Need Help Designing LED Tail/Brake Light

[ledsales]

Hello,
I wish to build a tail light brake light combo to replace the filiment bulb in my motorcycle.
I have made a couple of prototypes that came out ok but I wish to make it even better.
I will be using super flux LEDs for the next project and need to know how to figure out the maximum voltage that the LED can safely handle, the maximum will be used for the brake light function.

also I need to know how to figure the proper resistor to use to get the voltage down for the maximum for the brake light, and reduce even more for the tail light function.

I would also like to either add a strobe to the unit to flash 3 times each time the brake light is activated, or make the LEDs do this.

can anyone help me with this design?

Thanks
Jim

 

[Russlk]

The LED is a current operated device. The voltage does not change a lot (the dynamic resistance is low). You should compute the resistor to limit the current to the maximum that is stated on the datasheet. Using Ohm's law, R = E/I where E is the voltage across the resistor = supply V - diode V.

 

[HiTech]

Those "ninja" style crotch rocket bikes already have taillights like that. I think it might be Kawasaki that uses them, dunno for sure. You might want to check it out at the dealers since those lamps are already available and might be easier and more cost effective to simply buy one!

 

[ledsales]

Thank you for the heads up on the pre existing lights, BUT, thats no fun, I want to build my own, bigger better brighter...

 

[Sceadwian]

Just light a road flare attached to the the brake light housing when you need to stop... That will warn other motorists to immediately distance themselves, just like the same ultra bright red LED module would.
It's a road vehicle it is NOT A TOY.

The object is not to cause the person behind you to drive off the side of the road screaming in pain because you have an assembly on the end of your bike that shoots lasers at their eyes to alert them to your presence. It's brighter than dim for brake, and dim for running. Dim can be considered anything that can be determined to be brighter than full light on the reflector during noon on a cloudless day.

 

[audioguru]

The comedians are the guys who don't follow the rules for vehicle lighting.
Some of them blind people behind them but can't be seen off-axis.
Others are so dim that they are not seen at all.

The real motorcycle jokesters are the ones without a muffler, just straight extremely noisy pipes. They should be shot and hanged.

 

[Sceadwian]

So I'm bitter =)
I drive 18 miles to work, and 18 miles back, from suburban to highway to city drivers twice a day, once in the opposite direction if your counting, plenty of city errands during the day. I've been in front of, or behind, a driver of something that has a little bigger, a little better, or a little brighter more than most to know that if you're paying attention to that, you're not paying attention to something else, like the road or traffic conditions.

I'll tell you what.
You prove that a brighter running/break light on the back of your bike will make you a safer driver and I'll build it for you if it takes me a week or three of research and two hundred dollars in cash. Tell me cause you want bigger better and brighter and you're gonna get a commedian =)

 

[ledsales]

So I guess it is best I just Drop my project?
Im not out to blind anyone, If I wanted to do that I would just go with the factory made Xenon halogen and a Red lens with no fluting.

I wish to Gain Help from this forum in building the LED I described above, if this forum is not for help with electronics, well then I misunderstood the forum title.

If I would be better off to leave this forum because you think I wish to cause a hazard on the road, maybe I should.

What I was trying to do here is to make a bit safer tail/brake light for vintage motorcycles as they just have 1 little 1157 filiment bulb, to your cars 2 to 4 1157/3157 bulbs and the high level center brake light.

what did you guys think I wanted to do, put aircraft landing lights on the brake circuit?

so if You will kindly give me a break here maybe I can find some help with this project

Sorry If I trouble you guys,
Jim
www.lednights.com

 

[MaxPower!]

So I'm bitter =)
I drive 18 miles to work, and 18 miles back, from suburban to highway to city drivers twice a day, once in the opposite direction if your counting, plenty of city errands during the day. I've been in front of, or behind, a driver of something that has a little bigger, a little better, or a little brighter more than most to know that if you're paying attention to that, you're not paying attention to something else, like the road or traffic conditions.

I'll tell you what.
You prove that a brighter running/break light on the back of your bike will make you a safer driver and I'll build it for you if it takes me a week or three of research and two hundred dollars in cash. Tell me cause you want bigger better and brighter and you're gonna get a commedian =)

Hey this is not a new idea. LOTS of manufacturers use LED taillights from the factory and pretty much every other one has aftermarket ones available, many designed with making the bike more visible in mind.

What 99% of non-motorcyclists don't realize is that THE #1 greatest danger for a biker is car drivers that who aren't aware of motorcyclists. The light isn't intended to make him a safer driver, it is intended to make him more visible.

Sorry I can't answer any of your questions, although you might want to check out a few motorcycle forums. You could probably find an example of what you're looking for in one of their tech sections.

 

[ledsales]

I have A vintage mint condition 1975 Gold Wing, It has both Mufflers, Brand new even, you can barely hear it run at all, I like quiet.

the reason for this LED with a triple pulse on the break function is this.
there are very many rear end collisions where the Motorcycle is rearended.

the problem is that the general public is always too busy multitasking to pay proper attention on the road.

the vintage bikes like this one only has 1 1157 tail/brake light, barely noticable unless you are watching the bike closly.

last month one of our members was struck from the rear, wasted the bike but he was ok. the lady said she did not see him stopping, all I want is a light that is noticable to the every day driver that is used to seeing the 2 to 6 brake lights on the modern vehicles plus their high level brake light. these vehicles are very noticable in traffic, and the vintage bikes are not, their tail lights are very low to begin with, and the design is not so good either.
all this makes for an accident looking for a place to happen, we just need a little help here fellas.
If I wanted to be inconsiderate I would install a factory made xenon unit with a non fluted red lens, now there is a spot light.....
but im more considerate than that.

Jim

 

[ledsales]

Hey this is not a new idea. LOTS of manufacturers use LED taillights from the factory and pretty much every other one has aftermarket ones available, many designed with making the bike more visible in mind.

What 99% of non-motorcyclists don't realize is that THE #1 greatest danger for a biker is car drivers that who aren't aware of motorcyclists. The light isn't intended to make him a safer driver, it is intended to make him more visible.

Sorry I can't answer any of your questions, although you might want to check out a few motorcycle forums. You could probably find an example of what you're looking for in one of their tech sections.

Yes I am a member of many Bike forums but none have the skills needed, same as I.
I came here because it sounded so professional, I thought I could gain some great info from a site like this.

Thanks for your reply
Jim

 

[Sceadwian]

Ledsales, you should have probably mentioned that during the original post then, or at least at some point shortly after that.. Warning someone of the obvious dangers of simply going 'bigger brighter' with no reason in mind should not qualify someone as a comedian =) It was a simple concerned viewpoint with very good reasons behind it, to a user with no track record in the forums ask broad baseless questions.. All four of your posts have been in this thread.

 

[audioguru]

I know the problem of having just a single rear light bulb. The brake filament burns out and there isn't a backup one like cars have.
The center high brake light in cars is also missing on motorcycles.

So motorcycles are a hazzard at night and should be banned.

 

[cadstarsucks]

I have A vintage mint condition 1975 Gold Wing, It has both Mufflers, Brand new even, you can barely hear it run at all, I like quiet.

the reason for this LED with a triple pulse on the break function is this.
there are very many rear end collisions where the Motorcycle is rearended.

the problem is that the general public is always too busy multitasking to pay proper attention on the road.

the vintage bikes like this one only has 1 1157 tail/brake light, barely noticable unless you are watching the bike closly.

last month one of our members was struck from the rear, wasted the bike but he was ok. the lady said she did not see him stopping, all I want is a light that is noticable to the every day driver that is used to seeing the 2 to 6 brake lights on the modern vehicles plus their high level brake light. these vehicles are very noticable in traffic, and the vintage bikes are not, their tail lights are very low to begin with, and the design is not so good either.
all this makes for an accident looking for a place to happen, we just need a little help here fellas.
If I wanted to be inconsiderate I would install a factory made xenon unit with a non fluted red lens, now there is a spot light.....
but im more considerate than that.

Jim

What kind of tail light were on the bike? Incandescents take a some ~300mS to light. LEDs alone would substantially increase rider safety in that event as they come on instantaniously.

The next step would be to choose brighter LEDs, and beyond that to PWM them further triple the appearent light output.

D.

 

[audioguru]

motorcycles should be banned?

Yes. Ones with only a single burned out light in the back and ones without mufflers.

My streets are nice and quiet and are safe today. Because the streets are covered in ice and snow so there are no dangerous and noisy motorcycles out.

 

[Andy1845c]

Nothing but spam? Huh? Nigel and the other mods do a kick ass job of keeping that stuff at bay.

Everything you asked in your first post has been asked many times here. Use the search feature and look up LED breaklights, Look up PWM for the dimming. I have seen many sites on the web dealing with this also.

I personally wouldn't find it as easy to hang around here if it wasn't for the humor. There is a wealth of good info here, as well as a few laughs

 

[audioguru]

We have fun here laughing at little kids and their bicycles. The "little kids" have huge beer-bellies and long grey hair. The bicycles are noisy motorcycles.

 

[Andy1845c]

Geez, people have tried to help you, but all you do is get bent out of shape over a little teasing.

 

[audioguru]

He should drive a unicycle. It would look funny when the brakes are on hard.

 

[audioguru]

I have never had long hair and a big beer belly. I have lots of hair and a small bald spot. My hair is half grey.