Age old question: Charging

[Blurredman]

Hiya guys!


I'm very aware that I am somewhat flooding this forum with problems that I later resolve myself but this is one that gives me a little trouble. The bike is still usable, but in a state of a very thin thread of wire sort of way. As you know, a discharged battery on an MZ means you are going nowhere!

Esspecially when I've bought such a basket case where a new thing seem to be going wrong every fortnight.


Basically, the bike discharges the battery at idle. When riding around 2k+ plus application it charges the battery enough, and charges up to 14.5V or so when you really wack the throttle open. It doesn't over-charge.



If the bike is under 1.5k rpm then the battery discharges.
At 1.5k rpm-2k rpm the battery is stable, not charging, not dis-charging.
Anything over 2k and the battery gets charge.


The bike has a few modifications, some of them were present when I got the bike. The only major thing I have done is install an electronic ignition which is wonderful. My points no longer stick open randomly, and there is reliability in normal usage.


The bike has a replacement electronic regulator in place of the mechanical regulator.. I've noticed that this electronic regulator only has three connections those being DF, 61 and D- (D). I've spent the last hour seriously looking at the wiring and checking it is all in place, including re-making connections from the generator up to the diode plate.
I did notice that unlike the mechanical regulator the electronic one does not have a the equivilent of D+ or 51 connections.

The 51 connection looking at the diagrammes and manuals you connect the battery positive via fuse box, the D+ is an intermediary wire between the regulator and the D+ connection on the diode plate. Instead, the D+ on the diode plate goes straight to positive on the battery.... Is this right??? Could this be at all a cause to the lack of charging at lower RPM.


If not, what else could it be do you think??? The electronic ignition alone is quite greedy on the power so I rarely mess around after getting the bike started, and it is a very fine situation to be in.

[DAVID THOMPSON]

if you have room to fit it a battery with a larger amp hour rating that may help ...
if the system has brushes make sure there in good order and where they rub is clean
number 12 wire in good order on the plus and minus sides of the charge circuit
if it is a solid state voltage regulator they can have a bad rectifier diode in them and still work
there are 4 diodes in there if one fails open the thing still works but at reduced output

what is the ah of the present battery it may not be storing up enough energy to carry the system
if your spending a lot of time idling in slow traffic
also read what the original manual says about idle speed (tick over) a slow idle sounds great
but can kill a engine you can slow an old bmw motor down to very low rpm and it sounds great
but then it ruins the crank because it does not oil proper
if the 2 smoker mz has an auto lube pump it will not oil very good either....
DAVE
if you live where they now require HEADLAMP IN DAYTIME consider running led lamps in tail lamp and run a led in the parking lamp front
as a day time light to cut power use
i never met a bike that did not need a bigger better charging system

[Blurredman]

Hi.

The things you mention are those I have taken in account including the fact that the regulator may be 'kaput'.

I have the book stated 9ah battery. It's not the best anymore but it was in my previous MZ (points ignition) and had no issues there, likely because the bike's ignition is working properly on that.

I spend sometimes up to a minute idling in traffic, and aware of the fact that doing so discharges the bike I have increased the idle. Though it does look and sound quite unprofessional. I have it idling at 1,500 rpm instead of the book stated 1,200. I am well aware of using the proper idle speed. For example the CX500 needs to be at least 900rpm for the oil pump to be at it's most effective.

I am using pre-mix, not that that makes a difference really.

I always ride without headlamps on. It is not a legal requirement and I am vehemently against using them in the daytime regardless. A few nights ago I went on a 150 mile ride from 2am-5:30am where obviously I used the headlight, tail light and instrument lights. The bike was however always in motion because of lack of traffic. It did inspire confidence in the bike, but I now realise why the bike would seemingly randomly stall at lights before I installed the electronic ignition. When the bike stops, the points used to stick open. I attributed to the stalling down to the points not closing. Now I know it was likely due to the charging system.



What is people's opinion that it is definitely the electronic regulator and nothing else at fault?? I am going to swap in the mechanical regulator from my other MZ and see what happens then.

[Blurredman]

Okay guys..

So tonight I did this:


First I swapped the voltage regulator with my known working one. Same thing.
Then I swapped the diode plate with my known working set. Same thing.
I then swapped the battery with a year old battery that is good. Same thing.



I am completely flumoxed, and I right in thinking the only thing now that it could be is the rotor windings or stator??

I definitely noticed that the volts drop .20 volts every second just with the ignition system turned on....! Is it just the electronic ignition depleting the system so much when the ignition is on and when it is idling...???!!!? Surely not!?

I suppose tomorrow I'll swap the stator and or rotor winding....

How does the generator work? I understand it might be a three phase system. Does that mean there are three phases of voltage output depending on RPM and current drawn? Not very good with alternators other than the fact that the major componants like diodes i've already replaced...

Please help me This is my commutor. Haha. Though the nights are drawing in fast.. It won't be long before I start riding home in the dark and what with idling alone drawing current, idling with lights on is just not going to be an option!

[DAVID THOMPSON]

check this site

http://www.dansmc.com/

dave

[Blurredman]

Hi.

I'm going to be looking at the rotor when I get home. It's a possibility a connection or badly graded graphite slip rings are perished? The brushes themselves I checked when i first had the problem. They were good condition, and Plenty of life too.

[Blurredman]

Okay.

Well last night I changed one at a time: The rotor, the brushes, then the stator. All of them are fine. The electronic box itself is what is drawing the power. I've gone back to the manufacturer to ask why it draws so much power and whether anything is wrong with the unit itself.