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Madathlon
05-23-2014, 12:31 AM
(fixed) I have and 2008 Roketa MC-04-150Y with and GY6 150cc engine/drivetrain.

When I got the scooter the headlight where blown out and after much research I found LED replacements for it. when idling the lights are super bright and look great. but as I apply throttle they flicker and go out. (But the rest of the lights keep working)

Now I know that the Light are directly driven by the motor gen. but after studying the voltage I find it drops below 10vDC (Below the LEDs Limits)

I have considered changing the headlights power source from motor (Voltage Reg) to Battery off of the key sw.

Will this be on okay or to much an draw on the Battery?

ng5y
05-23-2014, 08:09 AM
[QUOTE=Madathlon;527552]I have and 2008 Roketa MC-04-150Y with and GY6 150cc engine/drivetrain.

I would be checking both the voltage regulator and the stator.

twowheeler
05-23-2014, 09:24 AM
LEDs are know to flicker when not running directly off the battery. Perhaps the bulb is defective since its doing more than just flickering. I would use a halogen headlight.

Madathlon
05-23-2014, 10:00 AM
I would be checking both the voltage regulator and the stator.

OKay, So what should I be checking for? I do know the Stator/Reg are charging the battery (I installed an Stereo that battery direct and its still charging) and the Reg seems to be working in the fact that it is charging.

So what should I be looking for? If there is a real problem I want to fix it but I am not replacing good working parts on an whim they might be broken.

LEDs are know to flicker when not running directly off the battery. Perhaps the bulb is defective since its doing more than just flickering. I would use a halogen headlight.

LEDs will shut down (As mine are doing) when the voltage drops below their limits. Halogen like standard bulbs will just go dim. LEDs are also much lighter on the Electrical system leaving more power for the scooter coil.

bnc
05-24-2014, 04:18 AM
If you measure the battery voltage before starting the scooter what do you measure? It should be around +12.8 volts. What do you measure after you start it? It should be above +12.8 volts at all rpm, more like +13 to +14 volts. If it drops below +12.8 volts at any rpm then something is wrong most likely the regulator.

I have had two regulators that charge fine at idle but at higher rpm, the regular failed causing the battery to discharge. One of them was around 2,000 rpm. It would be charging at 2,000 rpm but by 2,200 rpm it was discharging the battery.

There should be no reason why the voltage to the headlight should be +10 volts. It should be close to the battery voltage.

Madathlon
05-24-2014, 09:42 AM
If you measure the battery voltage before starting the scooter what do you measure? It should be around +12.8 volts. What do you measure after you start it? It should be above +12.8 volts at all rpm, more like +13 to +14 volts. If it drops below +12.8 volts at any rpm then something is wrong most likely the regulator.

I have had two regulators that charge fine at idle but at higher rpm, the regular failed causing the battery to discharge. One of them was around 2,000 rpm. It would be charging at 2,000 rpm but by 2,200 rpm it was discharging the battery.

There should be no reason why the voltage to the headlight should be +10 volts. It should be close to the battery voltage.

Except that the feed power from the Reg is AC (Not DC) and feeds only the headlights. My DC side of the circuit works just fine and puts out a steady 14.3vDC.

I done some research and it seems to be a common issue with LED headlights on these chinese scooters. The AC feed the headlights directly to solve a few issues, one legal one of always on. second the standard and Halogen headlight are power hungry. A 35/35 watt incandescent headlight and a 35/35 watt Halogen bulb draw the same amperage and volts something like 10/20 amp (Low and Hi setting) So using AC means the same (Cheap) wiring can handle a higher amp load) But LED bulbs of any form draw so much less Amperage. Mine are rated at 7 amps max.

So since every other light circuit is battery driven I am going to install an relay and rewire the headlights to a battery circuit this morning.

Madathlon
05-24-2014, 05:46 PM
OKay, So I tore into the Scooter. Now here what I found. The Headlight, Dash and marker lights were all driven from the AC side of the Voltage Reg.

So here what I did.

After removing all the plastic I found the AC feed to the Hi/Low switch and cut it.

I then went to the main SW and found Consent 12vDC and switched 12vDC. Then I found an goos spot to mount an 12 VDC Automotive 5-Pin Relay SPDT.

I used 12g wiring and wired the relay into the main SW so that as I turned on the scooter the headlight with received power now from an independent 12vDC power source. and then from the relay I ran a wire up to the Hi/Low switch.

So there the easy fix to the flicker issue.

bnc
05-24-2014, 09:21 PM
Oh I see what you mean. They use the the AC side of the voltage regulator, have a diode somewhere that converts it to an unregulated DC which is why there is flickering.

I have a bike where the manufacturer does something similar to what you are doing but they do this. They use the unregulated DC to turn on the relay which then connects the battery/voltage regulator output to the headlight. That way, the headlight remains off until the bike starts saving all the battery energy for the starting process.

Madathlon
05-24-2014, 09:24 PM
Oh I see what you mean. They use the the AC side of the voltage regulator, have a diode somewhere that converts it to an unregulated DC which is why there is flickering.

I have a bike where the manufacturer does something similar to what you are doing but they do this. They use the unregulated DC to turn on the relay which then connects the battery/voltage regulator output to the headlight. That way, the headlight remains off until the bike starts saving all the battery energy for the starting process.

I had thought about that, but with the unstable voltage the relay would also be unstable.