charging

en7jos · Post by **en7jos** » Mon May 09, 2011 1:00 am

The ammeter goes positive with the brake light on? Really? I've never noticed that!

Surely you would only be applying the brake when the engine was at (or nearing) tickover speed at which rpms it's not actually engaged in the charging system by the regulator (not enough volts coming out).

The horn and brake light aren't usually connected via the ammeter (anyone know why this is, always seemed odd to me but guess there must be a reason behind it?). So the ammeter won't show a discharge with either of them on, but I can't see why it would show a slight charge either.

As others have said, it all comes down to how good and well charged your battery is - a fully charged battery won't take any extra charge and hence no positive movement on the ammeter. So why not leave the headlights on for 5-10 mins to drain the battery a bit, then go for a ride again and you should see some charge all being well?

Otherwise all sounds like it's working as it should be to me, especially it the lights are still going after an 80 mile ride!

mossop · Post by **mossop** » Mon May 09, 2011 10:06 am

Hi All

Thanks everyone for all your comments and help on this. Andy, i did what you suggested and locked my self in the garage late last night and sure enough the lights did go bright when the engine was revved so im now happy that there must be a charge.

regards

Peter

Samuel · Post by **Samuel** » Mon May 09, 2011 12:16 pm

quote:
i did what you suggested and locked my self in the garage late last night and sure enough the lights did go bright when the engine was revved

Aren't you risking carbon monoxide poisoning

aobp11 · Post by **aobp11** » Mon May 09, 2011 2:42 pm

James/en7jos, the ammeter shows positive charge current when you press the brake and when revs are high enough. Just try. I first noticed this while the spring from stop switch to brake rod was at a large angle w.r.t. the the rear swing arm. Then with luggage and uneven road the stop light would switch on irregularly though the brake pedal was in rest. My first thought was of a shortcut somewhere between wiring and frame!
The stop light draws battery current. This would decrease battery voltage immediately because of voltage drop in the internal resistance of the battery. But this is sensed by the regulator which tries to maintain battery voltage at the same level. Hence the regulator sets the dynamo for more charging current.
Albert

mirangi · Post by **mirangi** » Tue May 10, 2011 2:21 am

Guys,
Get a cheap multimeter, put it across the battery, set to DC volts range.

Motor stopped, all electrial loads off, voltage will be about 6-6.5 volts (12-12.5V) start the motor and voltage should rise (to 7 - 7.5 volts (13.5-14v).

Switching on the lights (especially at Idle) will cause the voltage to drop but this depends on the actual revs at the time.

Note: Any rise indicates the bike is charging, voltage should not keep rising at high revs as overcarging will occur (This indicates regulator failure/ poor adjustment).

Steve

rex.webb · Post by **rex.webb** » Tue May 10, 2011 7:14 am

Scroling down this Forum Topic is a
"WONDERFULL VIEW of the WORLDS FLAGS" !.
Makes you realise how our
" BIKING ENJOYMENT"
is enjoyed all over the world. How Wonderfull if the Manufacturers could be back in buisness to see it ?.
Ride with Care and LIVE LONG to ENJOY our BIKES!.

Tommy RE · Post by **Tommy RE** » Mon May 23, 2011 5:35 pm

If it is any help, I attended a show at the weekend with my G3 and forgot to switch the headlight off (penalties of riding a modern bike and a combination of senior moments) I too had noticed that the ammeter on my bike showed 8 amps discharge when at rest and just went back to zero when the engine was under load. I too did the rev it up in the dark test and yes, the lights got brighter

I was gratified by the fact that when I got the bike running again after the show finished(amid comments from modern bike owners of 'You won't get that started with a flat battery'). Jaws dropped when on second prod the trusty old girl erupted into life, they obviously did not know about magneto power I was gratified on the ride home by the ammeter needle swinging to the right and showing a healthy 6 - 8 amps charge (Thanks Paul Dunn).

I agree with Spriddler about the wild swings of the ammeter needle caused by vibration when running normally. Good battery condition was established via my cheap Radio Shack multimeter that I bought from Tandy and have had for years (as miranji suggested above). So all in all Peter, I don't think you have anything to worry about

I shall have to give that brake light test a try, never heard of that one - just goes to prove you are never too old to learn something new. Enjoy the ride

Tommy

wilko · Post by **wilko** » Mon May 23, 2011 9:30 pm

Mine does the brakelight thing, which always made sense to me. I also discovered an intermittent short whilst riding by noticing the charging going to full swing to the positive on the ammeter when hitting bumps.