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Twigsoffury
07-27-2014, 12:51 AM
So I've recently come into owning a restored and modified 1977 Honda nc50 "Express"

https://en.wikipedia.org/wiki/Honda_Express#mediaviewer/File:1982_Honda_Express.jpg

(mines a bit different, but you get the idea)

But a problem with these scooters is that they blow traditional incandescent headlamps left and right, and being a vintage light, they're nearly 30$ a pop for something that sometimes only lasts a matter of months, there is a conversion kit to 5611 socket bulbs, but that only steps it down to 5$ every couple months and doesn't solve the problem altogether.

So what I've been thinking of, is using an assembly of LED's inside the original lamp housing.. in conjunction with a resistor capable of sustained over voltage (from high speeds since the engines modified..i'm guessing its producing more then normal current as well), but i'll sort of need help with the math once i figure out the various voltages and stuff involved. (still learning)

but i thought i could use something like this successfully?

http://static1.tme.eu/katalog_pics/1/b/a/1ba993c23d6a36db7bf768431b266345/hs10-470rj.jpg


anyways, stay tuned for some hilarity i'm sure =)

TheMainMan
07-28-2014, 09:58 AM
Sounds like fun! I'm sure it's doable and should be way more durable in the end. Any ideas for making sure your light is still as bright? Is the brightness for the original bulb a spec you know?

TLHarrell
07-28-2014, 12:59 PM
If you have a varying voltage input and a specific voltage you want to keep, use a voltage regulator. LEDs do not like to be overdriven, but you want to keep it near it's voltage maximum so it's not too dim. I wouldn't just go with a resistor because as the voltage changes, the current can change too and you're back to the same issue. *poof*

OvRiDe
07-28-2014, 07:39 PM
^ Agreed! What he said.
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Stonerboy779
07-28-2014, 11:22 PM
Best of luck with this would be good to see it come together

Twigsoffury
07-30-2014, 05:27 AM
=[

well how should i do it?

I was thinking of just making a whole separate lighting system that just runs off a RC car battery. 0_ o

TLHarrell
07-30-2014, 11:25 AM
Nah, that's the quick way out. To make it even easier, you could just use a flashlight. :facepalm:

I'll need the forward voltage, current and other data from the data sheets that come with the LEDs you want to use. I'm assuming these are very high intensity LEDs, not just some little 5mm packages. You'll need a heatsink to mount them on. Once you've got the data for their power requirements, selecting a voltage regulator and a few passive components (which are used to tell the voltage regulator what your needed voltage/current is) is easy. The whole thing can be assembled dead bug style, or on a piece of perf board.

Twigsoffury
07-31-2014, 02:46 PM
Nah, that's the quick way out. To make it even easier, you could just use a flashlight. :facepalm:

I'll need the forward voltage, current and other data from the data sheets that come with the LEDs you want to use. I'm assuming these are very high intensity LEDs, not just some little 5mm packages. You'll need a heatsink to mount them on. Once you've got the data for their power requirements, selecting a voltage regulator and a few passive components (which are used to tell the voltage regulator what your needed voltage/current is) is easy. The whole thing can be assembled dead bug style, or on a piece of perf board.


You are correct that i'm not using some standard PC style LED's. I've been looking at some drop in assemblies for Surefire flashlights that are about 530 lumin a piece ( i can fit a total of three in the housing, i figure one for low beam, all three for high beam) The motorcycle also has a battery underneath the seat that, but i haven't taken it out and looked it it yet... but i'm assuming that is what's used to power the lamps during idle and what not.

I also had the chance to see the headlamp working on another nc50, and it's abhorrent at best by todays lighting standards.. So i'm thinking we're pretty much sealed into the LED route at this point.

post moar later, as im in a rush.. byes!

Konrad
08-02-2014, 05:23 PM
A voltage regulator and some decent caps should work well. It may require heatsinks.

This application can use a thermistor in place of the conventional LED surge resistor.

A few questions you need to answer:

1) Is your intent to closely duplicate the output parameters of the original part, or to get the best output you can get within the electrical and physical limitations?

2) Are you planning to mount your LED assemblies within the "original" headlight housings to preserve vehicle styling, or are you planning to advertise your mod-savvy with overboard futuristic techno craziness?

3) What are the electrical characteristics of the existing headlight? And how much juice can your bike's battery sustain?

Twigsoffury
08-02-2014, 08:13 PM
This application can use a thermistor in place of the conventional LED surge resistor.

A few questions you need to answer:

1) Is your intent to closely duplicate the output parameters of the original part, or to get the best output you can get within the electrical and physical limitations?

Best output.

2) Are you planning to mount your LED assemblies within the "original" headlight housings to preserve vehicle styling, or are you planning to advertise your mod-savvy with overboard futuristic techno craziness?

Original housing, It's a vintage cycle worth quite a bit in the moped community apparently.

3) What are the electrical characteristics of the existing headlight? And how much juice can your bike's battery sustain?

6V at about 2amps? Not sure as I haven't cracked the seat off yet and looked.

Konrad
08-03-2014, 06:47 PM
Examine ratings of existing headlight bulb ... calculate (bulb Wattage) / 6V = (battery Amps) ... I'd think it's given that modern high LED assemblies will always not-less-bright (likely far brighter) than old bulbs when consuming the same power, so basically just concentrate on finding something that physically fits nicely within the original headlight fixture and doesn't yet doesn't exceed the rated Wattage or Amps.

Resistor/capacitor/regulator components will take up a little space, and may require an externally-exposed heatsink, but probably not much. Possibly integrated within the unit itself.

I'm used to working with 5V LEDs ... I have no idea whether 6V and 12V versions are available for automotive use.

Can't you just purchase a screw-in LED version of this particular incandescent bulb? Or possibly mod a standalone LED version into the screw-in receptacle of a dead bulb? Perhaps a better option if you intend to keep the original collectible value intact.

TLHarrell
08-04-2014, 12:07 PM
Problem he's having is that a typical screw in LED replacement would be rated for 6v operation. The nature of the charging system is that it will overvolt (to 7-9 volts range) and blow up the LED when going faster. A voltage regulator is by far the best way to go for this. You get rock solid 6v out of it regardless of the input voltage. It's basically a DC-DC converter. Anything above your selected rating it'll convert to heat (resistance). Anything below, it'll bring the voltage up by sacrificing current in trade. As long as you have more voltage/current supplying the regulator than the load is using, it'll work perfectly.

Twigsoffury
08-05-2014, 10:39 AM
Problem he's having is that a typical screw in LED replacement would be rated for 6v operation. The nature of the charging system is that it will overvolt (to 7-9 volts range) and blow up the LED when going faster. A voltage regulator is by far the best way to go for this. You get rock solid 6v out of it regardless of the input voltage. It's basically a DC-DC converter. Anything above your selected rating it'll convert to heat (resistance). Anything below, it'll bring the voltage up by sacrificing current in trade. As long as you have more voltage/current supplying the regulator than the load is using, it'll work perfectly.

hmmmmm......

You gave me an idea, and yeah i need a 6v specific LED array or bulb, and most everything is 12v or more.

The bulb also doesnt screw into the glass housing, its a sealed deal that it'll have to smash the socket and bulb out of, So really if i just mod the bulb itself i shouldn't tarnish the value of it.

http://farm1.staticflickr.com/133/421435618_09b9f967b0_z.jpg

Mines in way better shape, but that's the jist of what i'm working with.

Konrad
08-06-2014, 08:50 PM
Another approach, perhaps ...

A product like this 500-lumen bicycle light (https://www.serfas.com/products/view/732/) (also available in 750-lumen and 1000-lumen versions), about 70% of it's size is an impressive lithium rechargeable which can be removed in your application, it recharges via 5V USB connect and can function on 5V power without the battery (battery runtime at full intensity is only about 30-40 minutes, takes about 2 hours to fully recharge). LED assembly is basically a low-powered laser with Maglite-styled glass lens, all housed within a solid chunky metal heatsink armature thing; I happen to have the 500-lumen version and like it a lot, cost me about $65 but it's lasted almost 3 years so far and still going strong.

I betcha can find specs for a 6V-to-5V USB power supply anywhere online. You can probably just wire it up right through a standard 5V/1A 7805 part, I can provide circuit schematic if you need. Total part cost = bike light + about $2. Cheaper than replacing obsolete bulbs multiple times, at the very least you get to keep a cool bike light out of it.

Incidentaly - I really have no idea how many lumens a car or motorcycle headlight casts out. Anecdotal experience is that my 500-lumen lamp is about half as bright as a motorcycle headlight, I can see perfectly for about 100m on clear nights, see bright or reflective objects several miles away.

Twigsoffury
08-11-2014, 05:04 AM
Another approach, perhaps ...

A product like this 500-lumen bicycle light (https://www.serfas.com/products/view/732/) (also available in 750-lumen and 1000-lumen versions), about 70% of it's size is an impressive lithium rechargeable which can be removed in your application, it recharges via 5V USB connect and can function on 5V power without the battery (battery runtime at full intensity is only about 30-40 minutes, takes about 2 hours to fully recharge). LED assembly is basically a low-powered laser with Maglite-styled glass lens, all housed within a solid chunky metal heatsink armature thing; I happen to have the 500-lumen version and like it a lot, cost me about $65 but it's lasted almost 3 years so far and still going strong.

I betcha can find specs for a 6V-to-5V USB power supply anywhere online. You can probably just wire it up right through a standard 5V/1A 7805 part, I can provide circuit schematic if you need. Total part cost = bike light + about $2. Cheaper than replacing obsolete bulbs multiple times, at the very least you get to keep a cool bike light out of it.

Incidentaly - I really have no idea how many lumens a car or motorcycle headlight casts out. Anecdotal experience is that my 500-lumen lamp is about half as bright as a motorcycle headlight, I can see perfectly for about 100m on clear nights, see bright or reflective objects several miles away.


I've thought about that, and the local bicycle guy even busted out his best light for me in the back of the shop but its still no where what i think i'll need for a motorcycle.

100m is fine at 8~10mph, but its certainly not okay at 45+ on something with 70's drum brakes, Typical lumin ratings for automotive/motorcycle lamps are between 2,200~2,500, but that's for a pair, I also talked to a guy at Atomic Scooters here in the city, and he said Honda 600's also fit that style of honda housing, and they're around 8$ a pop.. He also sold me the OEM 6V battery for 18$ lol.

Lemme say, the battery size is extremely disappointing too LOL.

https://images.duckduckgo.com/iu/?u=http%3A%2F%2Fi.ebayimg.com%2F00%2Fs%2FNDk3WDUwM A%3D%3D%2Fz%2FeeMAAOxy63FS2DBJ%2F%24_35.JPG%3Fset_ id%3D8800005007&f=1


I'm Thinking I might go with some sort of hybrid set up, with high amperage RC battery packs (i've collected quite a few) and a set of high intensity LED lamps on the forks near the front wheel, then repairing the headlamp as it should be with an OEM bulb, then just putting in a simple switch to make sure its not running all the time so it isn't as susceptible to premature burnout.. if you get what i'm saying?

[edit]

This thing is also a super BLAST to ride around LOL

Konrad
08-11-2014, 08:29 PM
Well, a lot of people claim that size doesn't matter. I say they suck and they're plain wrong. You need a much manlier battery, lol.

Ah, I guess 1000-lumen won't cut it. But then ... who says you only need one lamp?

Twigsoffury
08-13-2014, 02:50 AM
Ah, I guess 1000-lumen won't cut it. But then ... who says you only need one lamp?


That's what made me think about using two wholly separate lighting system for average driving, and my actual third headlamp whenever i really need a lot of light.


Somebody also said I was doing 46mph today, in a 35mph zone, So i guess it is quite a bit faster then the original LOL

TLHarrell
08-13-2014, 12:14 PM
Somebody also said I was doing 46mph today, in a 35mph zone, So i guess it is quite a bit faster then the original LOL

This would be going downhill with a tailwind? And this somebody happen to drive a black and white car with fancy disco lighting on the top?

Twigsoffury
08-18-2014, 01:40 AM
This would be going downhill with a tailwind? And this somebody happen to drive a black and white car with fancy disco lighting on the top?

Driving next to me on a two lane road.

I also weigh 115lbs, (I'm my own stage II weight reduction)

It also has this https://www.treatland.tv/honda-hobbit-70cc-Polini-cylinder-kit-p/hobbit-polini-kit-119.0030.htm


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