Halogen headlight on 6V moby

I looked through the MA archives for info on 6V headlight options. It seems that 12V halogen bulbs will run pretty well on a 6V system because at higher rpms, well over 6V are generated. Also, it seems that the easiest bulb type to use is the MR16, as there are lots of different wattages, they come in 6 volt as well, and any hardware store has them for about 5 bucks.

So, after several trips to the autoparts stores, walmart and home depot, I found these chrome steel halogen lights at Wally World. Now, I don't like walmart. They sell crap. However, these lights actually seem pretty decent quality, and the price is right! $15 for a set of two. The chrome is nice, and the whole lamp is steel, the mounting bracket is solid, and can be tightened pretty tight. The light bulbs can be replaced in literally 30 seconds too. They are designed for cars so vibration shouldn't be too much of an issue. If it turns out to be, a rubber mount would be easy to fabricate.

So to mount them, I grabbed a bracket at the local hardware store:

Cut it up and drilled holes in the appropriate locations. I am using 2 of the handlebar mount holes in the tripple plate of my hobbit forks, and a third hole I drilled. The hardware that comes with the lights is 10mm, which is awsome!

I shortened the leads and hooked my ground and hot up by soldering and then using two layers of heat shrink tubing:

It is a small light; I was hoping to find something a little larger in diameter, but for 15 dollars for a set of 2, I think it looks pretty ok.

I haven't tested how bright it is yet; my bike is not quite ready to take outside and fire up. I turned the engine over with my cordless drill and the light lit up dimly, so I am pretty sure that with some engine speed it will be bright. Also, I am running a kit, so the 12v bulb will take the extra voltage. The only thing I have to do is get a lower wattage bulb; they come with a 50W but I think 25 or 35 would be more appropriate.

Re: Halogen headlight on 6V moby

Biggest pic thread ever!

Re: Halogen headlight on 6V moby

I want to high-five you for like 3 hours. I had been eye balling that same exact headlight for a month, but my mind couldn't wrap around installing it.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Yeah sorry for the size of the pics. But why sacrifice the detail for a little saved time?

Thanks Andy. I spent like 3 hours yesterday trying to find a simple and more importantly, durable and cheap solution. Found it!

Re: Halogen headlight on 6V moby

I'd love to know how bright it turns out.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

With any luck, I will have the bike running in a week or so, so I will update this thread.

Re: Halogen headlight on 6V moby

A+ thread

Re: Halogen headlight on 6V moby

dude, total awesome-ness. definitely gonna need an update once you get a trial run... i hope it is nice and bright. i love the idea of being able to change bulbs, too.. fuck a sealed beam.

if you get two with it, have you considered wiring them both up in paralell? thatd be a nice backup if just one isnt bright enough. you could mount them horizontally, but itd probably look less like a moped with eyes if you mount 2 vertically. shit, if you mount em vertically you could even work in a setup so you can have just high beam, just low beam, or both at the same time.

also whats your wiring like? hardwired? i dont see a zener diode, you ditch it? (side note, what do those things do and are they necessary?)

very nice work.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Steve,

The zener diode is like an overflow gate on a dam. When voltage exceeds the breakdown voltage of the diode, then current is allowed to flow to ground, lowering the voltage back down. It is a voltage regulator. It is necessary if you want to avoid blowing 6v bulbs, going down hills or using a kit (high rpms generate voltages >6V)

Brightness is not something I am concerned about. If the 12V bulbs are too dim, which I doubt they will be, then I can get 6V ones. Also, the power available to generate light is determined by the stator. Stock lights are bright enough, and halogen bulbs are much more efficient and bright, so it should work at least better than stock.

I considered using both lights, but I think it would look a bit excessive; If I had enough power to exceed 50w, then it would be practical to have another light, but I think you can only get about 20 watts out of the 6V stator.

The bike is hardwired. I removed all the stock wiring and replaced it with the absolute minimum. Next up is a tail light. LEDs should be in order here.

Re: Halogen headlight on 6V moby

hey carpy,

i've been messing with those lights for a few months now, i've got a set of 2 on a sachs, but i can't get the bike to power them at all, even just one... i ended up using a 12v rechargeable battery. they look awesome though even not lit. i attached one to either side of the headlight. and i'm working on a set to use as turn signals on a moby... keep us posted... i'll put up a pic of the sachs.

Re: Halogen headlight on 6V moby

You could probably run 2both lights with 6v ten watt bulbs. Or two higher wattage bulbs with different beams connected on a switch so you could select which one you want.

Re: Halogen headlight on 6V moby

Charles Cole (OFMC) /

What would happen if one of those 12v lighting coils was used? You know, the one that Treats sells. Would you also have to change the spark plug coil too?

Re: Halogen headlight on 6V moby

yesss that makes sense. i remember learing about zener diodes in high school electronics class... good simple voltage regulator. diverts excess current to ground. i'll remember to ditch mine when i hard wire :)

yea, another reason i mentioned running two is because (no offense) im not crazy how just the one looks. its a bit small for the bike, so having two might make it look a bit better. then again, if that thing is nice and bright i would have no problem running just one despite the looks. form after function.

Re: Halogen headlight on 6V moby

Great job Julian, and love the big pics. The non-perfect cosmetics of your frame inspires me to keep going on my slightly-rusty project. that bike looks pretty rad and I can't wait to hear how the kit and pipe run.

Anyhoo, about MR16's - I spec these in my architectural spaces (I'm a designer), but not very often because they have a very narrow beam. So, when you look for different bulbs, see if you can find a wide beam spread. The smallest is usually like 8 - but the widest might only be like 25. Also, hate to put another downer in it but I'm thinking 6V is going to be dim yellow but see what you can do with it.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Good point Mick, I checked, and the flood lights have a 36 degree spread, which I think will be narrow but still functional. Hopefully it works! I am also hopeful that the voltage is high enough to run it. I guess the only way to find out is a test! Just a cordless drill on the crank makes them light up dimly, and that is much slower than what the bike will idle at. Despite the cold, I think I might just have to gas it up and take it outside. Whether it will start or not is a good question though. I don't really feel like messing with timing in 10 degree weather.

Jasoncase, I wonder why the Sachs won't power these lights? Just not enough voltage? Do they even light up dimly?

cappy, I could not find a motobecane coil at Treats. Puch, yes, motobecane no. I suppose I could maybe put a 12V coil on from a 1980+ bike.

As far as looks go, I am not too concerned, as long as it works well. Just like anything, it will blend in after a while. In the mean time I can keep my eyes peeled for a good alternative.

Steve, I just can't see how two would look any better, haha.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

So, at 20 feet from the bulb, the beam would be about 13 feet wide. That seems just about right. A typical lane is about that wide, so at 40 feet it would light up most of the whole road. Good old trig functions

Re: Halogen headlight on 6V moby

julian,

if i disconnect the sachs main headlight and run one of these it will power it though dimly

this is the only photo i had on the comp.

<a href="http://s47.photobucket.com/albums/f187/lsaffron76/?action=view&current=S7300056.jpg"; target="_blank"><img src="http://i47.photobucket.com/albums/f187/lsaffron76/S7300056.jpg"; border="0" alt="Photobucket"></a>

Re: Halogen headlight on 6V moby

sorry about the double photo, notice the SWEET R.I plate i got by total chance

Re: Halogen headlight on 6V moby

haha true, 2 might not make things any better.

whats the current run status of your bike? can you get it going just to idle in your garage?

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Steve

This bike is in my basement. I don't have a garage. So, I can't really start it inside. However, I guess I could get a little shop vac with an extra hose, and put it outside through the window, and then wait for my roomate to leave, and fire it up inside. We have neighbors on each side of us, only a wall between. They would wonder what is going on. Although gasoline in the house is a BAD idea, so nix that one. Most likely I will just take it outside and brave the cold.

Re: Halogen headlight on 6V moby

yea no garage either, it sucks. i use my basement as well.

either option works, though.... if youre just firing it up for a couple seconds to check the lights it should be no big deal in your basement.

you're only gonna run it for a couple seconds, right? no excessive revving, however tempting...

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Oh yeah, I would NEVER rev it. Why would I do that??

God good I don't know why everybody revs their mopeds. I see it all the time. People driving mopeds down the road, with the engines all running fassst

Damn

Winter is a big anus this time of year. By the time feb gets here, I am tired of snow.

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Good news, I think. I got my bike out for the first time ever today, and the headlight is pretty bright even at idle. As soon as it gets dark I am going to go test it and report back. Oh, and by the way Malossi 62 wins. Yay

Re: Halogen headlight on 6V moby

I did something like this on my mb5 ^^

Its wired without a battery and lights them fine

untill I hit the brake light...

1233955712_mb_at_home.jpg

Re: Halogen headlight on 6V moby

Emperor Swagustus /

Update!

Finally got my ped running decently, and got to drive at night. Or was it night? I couldn't tell because my headlight was SO BRIGHT!

This setup works great. Mick and I were concerned (see above) that the beam was too narrow, but actually the opposite is true. I am running a 25W 12V wide angle bulb, and it is definitely more than wide enough. I am going to pick up a 35W narrow bulb tonight and give it a shot. Also considering mounting the other light, one with a wide angle and one with a narrow.

Also my LED tail light works great, 7 bucks from walmart..

Pics on their way

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