Adding an extra front light on a Vivacity 2014

[morphex]

Hi.

I'm looking to add an extra front light to this scooter, to light up more of the road surface now in the winter months, and I guess it is good to have it in general.

The existing front light is always on, and I can select a mode that gives more light further away, or a mode that uses both near and far (passing).

I'd like the extra light to be always on, as long as the motor is turning as with the existing front light; if that's not easy, it can be on as long as the ignition is on.

Is it as simple as connecting to existing wires, or do I need to use something to block current going through the unused wire from the new lamp back to the main lamp?

It comes with a switch I can mount on the handlebar, but it is a scooter and there isn't any extra space there.

-Morten

[pili]

You could wire a second light in parallel to the headlight, but beware as scoot stators are barely equipped to run the existing lights and charge the battery simultaneously. I noticed after doing the headlight mod on the Zuma that the draw of running both headlights on high beam changed the charge state of the battery a bit.

[FrankenMech]

The best way of running another light in parallel is converting both to LED lights with about the same combined current draw as the original light. Make sure the LED lights have their own rectifier and voltage regulation circuits. This is usually reflected by a wide approximately 10-30V operating voltage. The load on the electrical system must stay close to the same because the stator output is limited and the regulator relies on the headlight system to carry some of the output heat load. In a normal scoot a burned out headlight will destroy the regulator and a bad regulator will destroy the headlight. It may take some searching for an LED bulb that matches the original headlight configuration. Scoots may have somewhat odd headlights. I have found that cheap 10A 50V diodes make good blocking elements for the headlight wiring. Digital volt meters do not measure the headlight system voltage correctly the really ragged waveform fools them, you must use an old fashioned analog meter with a pointer needle. You can still buy analog meters that will do the job at some electronic shops or Amazon for $10-20.

[morphex]

Yes I was wondering about capacity, it's got a 90W alternator, 35/35W standard for the front light, and I guess 35+35W in passing mode.

Then there's the rear light which is probably 5/21W, then the blinkers on occasion, some misc. electric and the coil.

Does anyone know what the coil uses in current?

Is a 50V diode necessary? Isn't there a voltage regulator after the rectifier? Or are you saying that 50V diodes are cheap and just as good as a 20V?

[FrankenMech]

Both high and low beam are probably not ON at the same time. Use 35W combined LED power for your design.

The rear light and blinkers run off the battery.

The regulator contains a rectifier of sorts for the battery. The circuit is very poor and made for the absolute lowest cost on low end scoots. Some of the larger scoots use a real three-phase rectifier and regulator. I have no idea what your vivacity 125cc scoot uses. Some people have tried lifting the stator ground connection to try and make their own rectifier and regulator.

The ignition coil current is insignificant for your headlight project.

50V diodes are cheap and useful for 'projects'. I bought a bag of 100 years ago for my junk drawer so I use them for many things. I should buy some more, but I probably won't live long enough to use up what I have.

[morphex]

It's a 49cc.

In Norway, scooters come by law with a light that is always on. Near mode, low beam. Then you have a mode that gives better view in the distance, high beam, and then a third (which automatically goes back to near mode when released) that I think uses both, it seems the light is stronger and better than both other modes.

And that makes sense, because you should have some speed and need to see well when passing someone.

I was looking for information on the current the coil draws, but it is hard to find. What I did find was that car coils could use 7-8 amps, but this is a small engine with a plug that has a 0.6mm spark gap.

So is it safe to say < 1 Amps? 0.5?

[morphex]

For those interested, I'm going to add the light to the "high beam" cables, add a fuse and then use some connectors so that if anything tugs on the light cables, they'll give away at that point. The light will be mounted on the front mud guard.

It seems it won't be important to figure out the total wattage draw, as one light is 6W, lower than advertised, but I'll know for sure after testing the amperage.

[aeroxbud]

You should just run it through a relay from the light cables. That way there isn't such a large current draw on the light wires.

[FrankenMech]

Oct 25, 2024 5:46:42 GMT -5 aeroxbud said:

You should just run it through a relay from the light cables. That way there isn't such a large current draw on the light wires.

LOL, but the power still has to come from somewhere...

[aeroxbud]

Oct 25, 2024 10:58:55 GMT -5 FrankenMech said:

Oct 25, 2024 5:46:42 GMT -5 aeroxbud said:

You should just run it through a relay from the light cables. That way there isn't such a large current draw on the light wires.

LOL, but the power still has to come from somewhere...

From the battery. But you will not overload the light wiring. 😉

[FrankenMech]

The battery may not last long, depending on the drain put on it.

[morphex]

I'll just keep it simple, no relay, nothing extra.

FrankenMech said the coil (for ignition) was negligible in terms of power draw, so there's the head light at 35 watts, the rear light at 5 watts and some misc. power draw most of the time. Maybe 50 in total, rounded up. With the new headlight, 57.

The alternator generates 90W, so most of the time, there will be a surplus of 30W that can charge the battery.

Also, each head light beam draws 35W, the new lamp adds less than 18%, 6W to that.

[FrankenMech]

You are 'figuring' wrong, stop 'figuring'. Where did you get the 90W figure? System efficiency is low. The rear light may use 5W from the battery depending on the bulb used and the battery will barely charge that much. Just a little more current use will drain the battery. The regulator efficiency is very low and most power is lost to heat. The system requires that power to be shed in certain ways or the regulator fails. A burned out headlight will destroy the regulator. The system will barely operate as is. There is almost no power to spare unless you 'judiciously' shift power use within system capabilities. Your optimism adding up pie in the sky numbers is no good.

[morphex]

Well, if it is just the regulator that risks getting fried, I have a donorcycle of the same type which I can lift a regulator from.

The system is designed to support up to 70W on the front lights in passing mode, and I haven't seen any warning in the manuals for pressing down that for extended periods of time.

Also if there is a limit for what the wiring etc. for each beam mode, the current use is about 3 amps, and with this, it will be 3,5 amps.

Am I missing or not understanding something here?

[FrankenMech]

If the regulator fails the headlights will get very bright and then fail, many users here have experienced that. I recommend converting the headlights into high output LED lamps. They usually have internal regulation and rectifier circuits that will take 10-30VDC. Use LED headlights that consume close to the same wattage as the OEM bulbs.

You won't see many warnings in the manuals after being translated a dozen times. They are very inaccurate.