Honda/Huasheng/Titan,Lighting & Electrical System.

[skyl4rk]

I decided to stop work on the motor killswitch battery charger project. The issue is that when you use a bridge rectifier, the dc ground and ac must be separated. As soon as you tie the two together, the motor cuts out.

On the bike that i have, one leg of the ac is tied to the bike frame through the motor case and mount. So while it would be possible to keep the lighting and battery system completely separate from the bike frame, my lighting system is currently grounded to the bike frame. This is incompatible with the bridge rectifier.

I believe it is possible to charge a battery by using rectified dc from the kill switch wire. The amount of charge is likely to be a fraction of the amount used by the lights. A guesstimate is that the motor can provide between one tenth and one fifth of the amp hours used by the lights. So ride ten hours to light one hour, more or less.

To be more specific, at idle, I found 12 V and about 60 mA available without shutting off the motor. At higher rpm, the output was roughly double the voltage. I have had some trouble with my voltmeter so I am unsure about the results.

If I were to continue, I would connect the dc output of the bridge rectifier directly to a 10 pack of NiMH batteries in series, which runs about 12.9V. I would then run the bike and measure the temperature of the batteries to see if there were any damage being done to the batteries. I do not believe that this level of voltage and current would damage the batteries at all, their internal resistance would "regulate" the voltage and it would serve to charge the batteries.

Good luck to anyone who picks this up and runs with it. There is potential.

 

[fetor56]

Good if someone continues this project;for now i'm happy running a tail-light.

 

[duivendyk]

The battery does not necesarily have to be floating when you use it,with a dpdt switch you can disconnect it from the charging input and connect it to the light circuit.You have the black wire output still available to run the taillight as Fetor56 has done.How does that look to you? There are other options,but better one thing at the time.What I still don't know is wether or not you can actually charge a floating 12 V battery.Don't give up the ship yet.

 

[fetor56]

@duivendyk.
It looks quite good.....the flash of the camera interferes but it's easily good enough to be seen at night.
Daylight hours it can also be seen & since i'm safety conscious about being hit from the rear i'll stick with it till something better comes along.

 

[skyl4rk]

I copied fetor's LED taillight idea and can confirm that it works at idle speeds. I have not run at higher rpm yet.

I used a $7 LED clearance light from Tractor Supply. I believe it is similar to this type of light:

http://www.vehiclelight.com/1035.html

There appears to be only one LED in the light.

I did not disconnect the kill switch, just connected the positive lead from the light to the killswitch wire, and grounded the negative lead from the light to the bicycle frame (which is connected to the motor frame).

It puts out about the same light as a bicycle dynamo powered taillight. It is on whenever the motor is on. The motor starts cold OK with the light connected. The killswitch still works as usual.

I am very happy to have an always-on taillight.

 

[HoughMade]

I have a 7.2 ah SLA battery to power my lights- all the turn, stop and tail will be LEDS- very little draw. The headlight is currently a 50 watt halogen...big draw, but I may move to a 35.

I have designed the system to run a dedicated ground wired back to the battery rather than through the frame. I would like to trickle charge the battery with the engine and not run lights directly off of the engine...obviously there is not close to power for that. I suspect, however, that the trickle would keep the battery charged to run the turn and brake lights indefinitely.

I may pick this up.

 

[duivendyk]

Skyl4rk,as I pointed out before,it's NOT the end of the world that the battery has to float while you are charging it.If you do this in daytime you would not be using your lights anyway.All it takes is a double pole, double throw switch to disconnect it from the floating rectifier and run the lights with one side grounded, if you so wish,you'd still have the black wire output available then, to supply your tail light.The thing to do is to find a live 12V battery& find out if the blackwire output is able to charge it with the fullwave rectifier without untoward side effects.That would be nice to know.

 

[skyl4rk]

I'm still on it, just tied up with some situations and its c-c-c-chilly in the workshop.

I'm going to isolate the headlamp from the ground and tie the battery to the black wire through a rectifier. I will also have a solar panel connected. The tail light will be powered directly through the black wire, thats what I have going now.

I got an ammo box and am working on mounting it as a base for the solar panel and a place to put tools in.