Total Motorcycle Community Forums

I will try to answer as many things as possible all in one post.

Niterider, you said that maybe the reg/rec was not putting enough out. The thing is I tested the reg/rec and it was fine, as was the generator. As I had a spare system lying around(brand new and fully functional, it was attached to my CZ125 till the rear suspension collapsed) I switched the ignition parts, and the problem was stilll the same, though the battery charged fine on the CZ. One point however was that the CZ only used about 40W with all lights.



Flynrider, you said that if I have a generator... well, I think its a generator rather than alternator. Listed as following in the parts list:

Magnet based generator with integrated fully electronic ignition. Output 6V/100W DC. Solid state ignition with own power supply from within the system. Replaces old dynamo, points, condenser, ignition coils. You may drive without a battery, if you want. There is no need for changes on engine casing.
Thing is I know other people with same model Jawa, with the original generators still in (65W) so in theory I should be running an advantage.

As for lower wattage bulbs, I suppose I could. But I would hate to. 35W is not much for a headlight, and only just bright enough for night riding. I've already got 10W's in the indicators instead of the prescribed 21W'ers. And if I dim the tail light anymore it will be all but useless. So I dont know what to do.

OK. No Offense, but you are confusing the hell out of me

Let's go through it.

First of all - Your Charging System and your Ignition system are completely separate circuits. stop thinking of them as one and the same. If your battery is dying it's because of a fault in the CHARGING system.

Tyrone ORourke wrote: Niterider, you said that maybe the reg/rec was not putting enough out. The thing is I tested the reg/rec and it was fine, as was the generator. As I had a spare system lying around(brand new and fully functional, it was attached to my CZ125 till the rear suspension collapsed) I switched the ignition parts, and the problem was stilll the same, though the battery charged fine on the CZ. One point however was that the CZ only used about 40W with all lights.

A charging system that puts out DC voltage from a generator does NOT require a Rectifier. A rectifier only changes AC current to DC current which is required to charge the battery. If you have a RECTIFIER, then you have an AC generator. (Consisting of a Stator coil)

I'm going to assume you have an AC generator, because you keep mentioning a rectifier. In this case, the Answer to your problem is probably with your stator coil. An INSULATION BREAKDOWN in the stator coil will cause the Battery to discharge either while standing still or within a short time of the bike running. You need to test your stator coil.

Flynrider, you said that if I have a generator... well, I think its a generator rather than alternator. Listed as following in the parts list:

Magnet based generator with integrated fully electronic ignition. Output 6V/100W DC. Solid state ignition with own power supply from within the system. Replaces old dynamo, points, condenser, ignition coils. You may drive without a battery, if you want. There is no need for changes on engine casing.

I'm pretty sure what this is advertising is a Capacitor Discharge ignition system (CDI). If I'm right, CDI systems use an AC current (Rising field coils) to discharge spark. Therefore, the system must have an AC generator. They are advertising the charging output of 6 Volt DC because the system includes a rectifier.

If you do not know how to test a stator coil, get back to me and I'll tell you how. It would be easier for me to describe to you how to test the system if I knew which kind it was, however. If you ahve a digital camera, let me know and I'll ask you to take some photos of various components and send them to me.

If you do know how to test the stator, cheers and let me know how it turns out. Hopefully , this wil solve your problem.

Looking over your last response again, I also notice that you swapped components on the bike but left the charging system in place. Process of elimination tells us that the fault lies somewhere in the components that were not swapped (Stator coil being primary suspect)

Tyrone ORourke wrote:Flynrider, you said that if I have a generator... well, I think its a generator rather than alternator. Listed as following in the parts list:

I think TechBMW is on the right track. It sounds like you have an alternator with a permanent magnet (i.e. no primary field current required). If the original was truly a 65W generator, there would be no way you could run a 50W load and still keep the battery charged, unless all riding was done at high rpm. An alternator will deliver full output power at much lower rpms.

Whichever it is, the problem seems to be low output. Your comment that the battery charges OK with the headlight off, and will drain with the headlight on in slow traffic is an indication that the output is lacking. As Tech noted, if you've eliminated the reg/rec, the stator is now your primary suspect.

I'll try to keep things simpler this time. Im afraid I dont know much about electrics, so you will have to excuse me.


These links show pictures of the system I run. I take it that since the stator is there I have the AC generator mentioned.

http://www.powerdynamo.biz/deu/systems/ ... inpack.jpg

http://www.powerdynamo.biz/deu/systems/7150/statpos.jpg

It was suggested that I might have a faulty stator, and that could be. But I did replace EVERTHING except the coils of the working system. So I would think that the stator might not be the problem.

I am interested in the theory that the system is leaking though. I know that the charging systems are seperate from the spark system, but here is a new theory. The engine is shut off through a switch on the handle bars that grounds the coils, and thus stops the engine. Is it at all possible that this ground is leaking(due to a faulty switch) and letting the battery drain?

Don't worry. No one knows alot about electrics, that's why it's such a pain in the rear.

Thanks for the pics.

Charging System Static Testing

You're using a Full-wave charging system.

Your rectifier has four diodes in it. You need to test all four of them statically to make sure none of them are leaking back through the system. (You need an ANALOG ohm meter to test these pissers) Make sure the battery is out of the bike when you use your ohm meter!

You perform this test at the plug to the reg/rec.

RL = Red Lead of meter
BL = Black lead of meter
BW1 = Black Wire from Stator Coil
BW2 = Black Wire from Stator Coil
AC = Red Wire to Battery
GD = White Ground Wire

FORWARD TESTS Result on all tests should be 4 - 40 ohms
Test 1 : RL on BW1, BL on AC
Test 2 : RL on BW2, BL on AC
Test 3 : RL on GD, BL on BW1
Test 4 : RL on GD, BL on BW2

BACKWARD TESTS Result on all tests should be Infinite Resistance
Test 1 : RL on AC, BL on BW1
Test 2 : RL on AC, BL on BW2
Test 3 : RL on BW1, BL on GD
Test 4 : RL on BW2, BL on GD

OK, Static Testing the Stator Coil - This test is conducted w/ the ohm meter as well.

Test 1 : RL on BW1, BL on BW2 = roughly .5 - 2.5 ohms
Test 2 : RL on BW1, BL on GD = Infinite Resistance

I am interested in the theory that the system is leaking though. I know that the charging systems are seperate from the spark system, but here is a new theory. The engine is shut off through a switch on the handle bars that grounds the coils, and thus stops the engine. Is it at all possible that this ground is leaking(due to a faulty switch) and letting the battery drain?

The switch on your handlebars is closed when the bike is running There is no where for the power to go unless the relay between your coil and your ignition switch is shot. All your ignition switch does is provide power to the ignition relay.

Are you absolutely sure the rest of the electrical system is sound (Such as the headlight wiring?)

Just to follow things up. Sorry it took so long, my analogue multi meter disappeared, I left it in my car, but when that developed electical problems, I brought it to my electrician, who apparently took it, as thats the last I ever saw of it.

Nevertheless I finally got a new one, and the stator is fine

Considering that I went over the whole bike wiring with a fine comb and finnally found the fault.

The main grounding point is in some inaccesable place behind the airbox, so I've never seen it close up, but from looking at it, it always seemed fine.
As the airbox was off recently to fit the rebuilt engine back in, I took a good look at the grounding point. Turns out that the wires were grounded against a piece of plastic painted silver so it looks like metal at a glance, so the only grounding was through a washer on the bolt. Stupid stupid stupid!!!!

Anyway now that the ground is properly sorted out, everything is fine, the battery hasn't gone dead over 200 km of driving in lots of traffic, and never above 2000rpm(running in period, dont you just hate running in!!)

Many thanks for all the suggestions!

Tyrone

are you sure you don't have 12 volt bulbs installed in it by mistake? Did you test the electricial system with a paracitic load test? Do you have a VOM Meter with either a milliamp or millivolts range? Take the neg battery terminal off the battery connect the meter leads in a series you should read no more than 20 milliamps, you can also use a millivolt setting, a test light won't work, you need a meter. Remember, you have twice the amps on a 6 volt system than a 12 volt system.

I take it you guys do understand ohms law, as your voltage decreases your amps go up.