Can anyone explain the electrics on my 2007 EC250? (UK)

JAD

New member
2007 EC 250 in the UK

I am hesitating to ask this because electricity confuses me on a good day!

I have always had bikes with a battery before but this bike does not. Obviously no electric start and only basic lights (headlight, tail light and stop light). No speedo and the horn runs off its own little battery (looks like one off a bicycle)

The headlight dipped beam works (standard incandescent bulb) but nothing else.

So...

Is it a completely AC system? How do you get things like 12V horn, phone charger, and maybe LED lights to work?

Is there any way to check the wiring and voltages without having it running all the time...

Sincere apologies if (as I suspect) these are dumb questions... :)
 
You need a regulator/rectifier to turn the AC voltage from your stator to DC voltage(12). Are you sure you don't already have one? You could also measure the voltage at your headlight for example to see if it is 12v DC or if it is AC voltage. If it is 12v DC you already have a regulator/rectifier.
 
The system is entirely Ac except for the horn. They usually have a horn rectifier which converts the ac to dc.
There is a small zener diode which acts as a regulator for the ac voltage and ensures it does not exceed around 14-15 volts.
Most dirt bike run on ac lighting. It ends up looking like square wave Ac voltage which the LED light do not care about and will run fine on.
 
Thanks all, I have been investigating and the low beam, led tail light and brake lights work fine until I use the left handlebar switch to select high beam. High beam then works fine but the tail light turns off. Which is a novelty!

I am guessing that the tail light is powered from the low beam circuit and consequently turns off when high beam is selected. I shall investigate some more...

ps...what does the red switch on the right handlebar do? (all marking have rubbed off the switches) . I have traced the wires and they both go to what looks like a CDI unit under the seat.
 
ps...what does the red switch on the right handlebar do? (all marking have rubbed off the switches) . I have traced the wires and they both go to what looks like a CDI unit under the seat.

Most likely the map switch. Does it look like this one (on the cooler hose) ?
picture.php
 
Yes..same switch as that so I guess I have a map switch. It does not seem to do much mind?

No, it all depends on your jetting (in my experience). When I ran the Keihin (worn carb on my 06 model) it didn't really do much. But with the (properly jetted) Lectron, I noticed a difference. It will also depend on your squish band / head modifications, I presume.

On my '15 EC200, I run it in the "sun" mode all the time, an the 200 motor has just about perfect power for my needs.
 
It just retards ignition about 4 degrees. In the mud you will notice it is less likely to spin up. But it takes the bark out of it. Assuming it is still connected properly.
 
Thanks guys.
I cannot fathom out the lighting issue.
When the switch next to the left grip (looks exactly the same as the map switch) is on low beam all is well. Dipped headlight and tail/brake light all work.
If I select high beam with the same left switch the tail/brake light goes out.
Anyone have any thoughts...? The wiring diagram is not helping.


Sent from my LLD-L31 using Tapatalk
 
Solved... when the high beam +ve connector is removed from the bulb all is good. I think the left handlebar switch is just a single pole lights on/off and it was never designed for a high/low beam option. Hence when I connected the black lead to the bulb high beam the switch earthed out the tail lights..

I shall go the AC to DC route as described in the sticky.. Thanks all.
 
Hello,

The type of switch that you are using is the wrong type of switch , it is acting as an on - off switch .

Have a look on ebay for universal motorcycle light switch and wire your electrics to one .
 
2007 EC250 with just basic lights - (low beam headlight, tail and stop light only)


Ok, after much study and reading I have come to the conclusion that my brain is not wired up to understand electrickery!

The sticky post above (AC to DC) refers to the main earth, I have 3 in the same location by the ac regulator and it seems that all of the lighting earths need to be removed ...etc... I am confused...

So, I have two wires (one yellow and one white) which appear to come from the stator. The white wire goes nowhere (not connected to anything) and is just taped to the frame at the left side of the tank. The yellow wire has a spade connector and that appears to go to the ac regulator near the coil. Both these wires are live when the engine is running.

Is the following sensible /possible?

Leave the existing system exactly how it is but disconnect all the lights (and brake switch) from any earths to the frame.

Use the redundant white wire from the stator to power a new reg /rec earthed to the frame with the correct wire. I assume the reg rec needs to be earthed to the frame with its wire NOT bolted to the frame)

Will I now have a new source of 12 V DC from the reg rec which I can use for lights and other accessories? I appreciate that everything utilising this new 12V DC will need to be isolated from the frame. (I hope the brake switch will not cause an issue?)

Essentially I will have added a new 12V DC system which is isolated from the existing circuits and with its own earth/neg to a battery - all sourced from the white wire under the tank.

Is it vital to also have a battery on this new 12V DC system or will it work without?


Just smiling, as I suspect this will be jibberish to those electrical wizards out there... apologies!
 
The second unused white wire source coil will not have the power to run a Dc circuit by itself. Have a look at the topics here on floating the earth if you truly want to run Dc power.
Essentially both source coils the white and yellow ones are earthed to the stator plate. These are connected and then run to a regulator rectifier which then with supply DC power.
You will need a battery or capacitor to store the power.
I would just be fixing the Ac circuits and running that. Simple and it works. I do not know where you got the idea that you need to disconnect earths from the frame. Many bikes use both ac and Dc circuits and share common earths with zero issues.
 
Shared earths is an issue regarding how the voltage rectifier works. The GG stator is a simple single phase AC system. The windings are in series with the yellow wire being ~80% tap and the white wire being a 100% tap. The bottom end of the windings is grounded to the engine/frame.

Simple explanations regarding voltage rectifiers:
https://www.rohm.com/electronics-basics/ac-dc/rectification
https://www.ccontrols.com/enews/2018/0518story2.htm

On a GG the yellow wire is regulated to ~14 volts AC relative to ground. This is the most basic method for lighting. The filament in a bulb works fine whether it gets AC or DC voltage. The white is not used since the regulator would have to work that much harder to clip the excess voltage.

On the newer machines with estart, the white wire is used to feed the rectifier. The AC stator voltage on the white wire is rectified to ~14 volts DC.

Since the GG system shares the stator ground and the battery ground it uses a half-wave rectifier. This removes half the sine wave and the higher voltage on the white wire helps to make up for this loss. The lumpy output (more like a pulsing DC voltage) is leveled out by the battery.


A full wave rectifier is more efficient but requires isolation. Since the battery is grounded to make the starter system simple, the stator ground must be removed from the engine/frame ground. This is often called "floating the ground" and requires a modification of the stator. The bottom end of the windings is changed to only connect to a new additional wire. AC output occurs on the white wire and the new wire. This feeds into your full wave rectifier. There is still a reduced AC voltage between the yellow wire and the new wire but it is not used. This floating of the stator ground allows for a grounded output of the rectifier (required by the starter motor).

So why do we want DC voltage? Battery charging is the main reason. So if you do not add a starter, you really don't need a battery. Some juristictions may require a method for the lights to be on without the engine running, so that needs a battery. Horns and flasher relays also want DC voltage. Most everyone adds a battery since it's easy to do.

The simplest way to set up an electrical system is to leave the stator grounded and have the rectifier output ungrounded. Take this ungrounded DC power to just the items that need it. It will be there for all your devices EXCEPTING a starter motor. This mixed system will work fine if you hook it up properly.
 
Many Thanks Neil.. the penny has finally dropped!

"The simplest way to set up an electrical system is to leave the stator grounded and have the rectifier output ungrounded. Take this ungrounded DC power to just the items that need it. It will be there for all your devices EXCEPTING a starter motor. This mixed system will work fine if you hook it up properly."

This is what I was getting at and, will do, if the guy at the testing station insists on the letter of the law.

From your description I think I will be OK to use a full wave rectifier attached to the white wire... Electricity is funny stuff.... :)

Lets hope, for all our sakes, he just passes the bike!
 
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