MOPED ARMY

Right,Wayne! I remember I was wanting to know why I can run a 12V DC headlight and 6volt DC tail and brake light on my Sebring and not have any trouble.But you know;`A little knowledge is a dangerous thing' in some instances,and it takes some pretty good delving into to understand basic electricity principles.Especially when mopeds don't always play by the DC rules which I am so used to.You see,I was told that what the moped is putting out is not really AC,but higher voltage DC(it does not truly alternate as AC does).Now before you jump straight up,Ron,I said.... `what I was told was'.....,not `what I'm convinced of'.You see,Wayne,when I did concrete work,many times there was no electricity at the job site,so I bought a kit which provided 110 volt or higher DC?from the truck's alternator.IT WORKED GREAT!! I even jack-hammered 20 tons of concrete slab out one day with a heavy-duty electric jack-hammer.It would run drills,saws,light bulbs,or any tool with a brush motor(not induction).It was a tremendous help and ran straight off the alternator.I never had any trouble with it.

Wayne,

..laughs and blows coffee all over the keyboard..., I recall that thread, there was so much wrong stuff and mis-information, some of it from people who got their information directly from god, that I bailed.

I did, however, decide to try to write a simple electrical guide. Ken's info is good, anyone got an electronic copy of the basic electrics he is talking about?

Ron

The reason is because there usually is a DC circuit in a moped.

U.S. regulations from the late seventies specified a certain brightness to the tail & brake lights. Because the output of a magneto varies with speed, the lights on your bike would be dull when you were at a stoplight and the bike is idling and get brighter the faster you go. The way to stop this is to add a battery into the circuit, which gives a constant output. This way you can recharge the battery when your bike is traveling a high speed and the magneto is putting out more juice than you need; and then power the tail and brake lights with the battery when you are stopped and the output is low. One problem. A generator (magneto) produces AC current. Therefore you have to rectify the output, or convert it to DC to charge the battery (batteries are DC). Well, then why isn't the whole bike DC then you ask. This is because there are many losses occurring when you rectify the current and some things don't need to not dim. Sooooo, you use the battery system (which gives constant brightness to the lights) to the really important things like the tail and brake light that shouldn't dim at idle (important for safety reasons). On the other hand, the headlamp is relatively bright and large and doesn't need this type of treatment (Hey, I didn't say so, the U.S. government did - it is larger and brighter). So, there is a separate coil in the magneto that powers the things that can dim. You want to use AC current here because you can get away with it, it's simpler, the lights will end up bright enough anyway, and you would loose a lot of power in converting to DC. The horn can be DC or AC depending on the manufacturer. I have two of the same bike of different model years, and one has an AC horn and the other has a DC horn. I guess they just decided that their current setup wasn't what they wanted. Dunno. Although, I do admit, I do not know a lot about most of the brand bikes that y'all have, but all six of my bikes work like this. I think it is a rather "standard" setup. Hope this helps and isn't too confusing.

my battery has been dead for years. so my lights dim and then brighten ... so i think i have ac electrical? if the batter worked ... then it would be dc?

Miguel,

If you have a circuit designed for a battery, it is a dc circuit at the battery and the lights. What you do not have is a battery to absorb the excess output, normally used to charge the battery. The battery in a dc circuit acts as a voltage regulator, without it, the voltage can get high enough to burn out bulbs. This may be why you have a fuse box. Under these circumstances, a single fuse for the dc lighting circuit would protect all the bulbs, but I would think you would be blowing fuses all the time.

See my 15:30 post under this thread.

Ron

Miguel,

Sorry, I meant my 15:48 under "Sachs Westlake electrical problem".

Ron

Awesome post--wow-- thanks a lot.

Ken,

Great! Thats as good an explaination as I have seen. I especially like the tail lamp operation quirk. It looks like that could send you round in circles for a while.

Ron