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Posted By: Danam A50 charging system question - 09/29/19 12:17 am
Hello gents! Last week I was enjoying a ride on my A50 when it started to sputter and eventually stopped. My battery was dead, so I managed to get it back home. I put the battery on a charger, the volt meter said 13.0 volts. So I'm thinking its the charging system. i put the volt meter on it while running and the readout was all over the place. as high as 20 and as low as -1(??) I don't think anything is wrong with my volt meter, has anyone seen this, I am running a Podtronics.
Here's a video:
video of charging system on volt meter
Posted By: gavin eisler Re: A50 charging system question - 09/29/19 12:46 am
Try another meter. Do your lights get brighter with more revs? How old is the battery?
Posted By: Danam Re: A50 charging system question - 09/29/19 12:51 am
The lights do not get brighter when revving. The battery came with the bike (looks a few years old).
Posted By: gavin eisler Re: A50 charging system question - 09/29/19 12:54 am
Do you feel lucky?
If not get a new battery. Still worth trying another meter
Posted By: Danam Re: A50 charging system question - 09/29/19 1:10 am
I really dont think it's the battery or the volt meter
Posted By: quinten Re: A50 charging system question - 09/29/19 1:49 am
seen it many times with digital meters ( depending on their quality )
When the meter is connected directly to a Pod Tronics type regulator ... without a load.
(the meter is the only load )

All those jumping voltage readings are true , within the meters percentage of error
but only for the millisecond of time that the digital meter is sampling.

The digital meter is taking multiple time samples against a clock time .
But can't settle on a DC voltage ....because there isnt one stable voltage...only the
Various sample time readings .

the meter is reading the podTronics clipped output ... which is mostly off .
as it clips each half/ Hertz wave at ... close to 100 times a second ... at idle .
what gets displayed is the individual samples against the meters refresh rate .

if there is a load in the test circuit ...like a battery .
the error is as likely to be because
the meter needs new batteries .

Or the transistor noise from the podtonics is interfering with the digital meters electronic circuits .



Posted By: NickL Re: A50 charging system question - 09/29/19 7:32 am
It's the meter, believe me. Try an analogue type. I won't go into the science of it.

One of these will do: https://www.ebay.com.au/itm/Analogue-30V-DC-Voltage-Needle-Panel-Meter-Voltmeter-U5L6/264380876580?hash=item3d8e540724:g:x~gAAOSwECNdF2v8&frcectupt=true&autorefresh=true

If the lights don't get brighter when you rev the bike, either the regulator or the alternator isn't functioning correctly.
With a Pod, the charge threshold is set at around 14.5v. So that's what sort of reading you should get at 3000rpm.
Posted By: KC in S.B. Re: A50 charging system question - 09/29/19 2:42 pm
This thing is Really handy. You can just leave it attached if you like, as it will time out with no activity. (button press wakes it up if you want) Easy way to rev and watch the voltage change....
I'm a BIG believer in voltage with any electronic ignition bike, as amps don't help if volts are not up! Anyhow,........... my $.02!

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Posted By: Danam Re: A50 charging system question - 09/29/19 6:18 pm
That little battery tender volt meter is in excellent idea, I will get one of those. So I got me an analog meter and it shows no increase of voltage when revving, just sits about 12v. I disconnected the alternator wires and put them on the meter while running and it read 0.00 volts. Also, I connected each alternator wire to ohms meter, with other meter lead grounded to the frame. The meter read 1.0 ohms... so, what's next?
Posted By: KC in S.B. Re: A50 charging system question - 09/29/19 6:47 pm

I seem to recall you can't just check the alternator (AC volts) output as simple as that. There is a method in the Shop book to check the alternator, and I think it required a large resistor. I did that years ago and have it somewhere. Just looked back, you have a Podtronics, and those are usually good parts, I use them also. The posts where you said the readings jumped as high as 20 sounds like the Alt must have been doing something. Digital meters no help with this, so as already said, analog meter, CHEAP at Radio shack, etc. Did you say how old the battery is?
Posted By: Danam Re: A50 charging system question - 09/29/19 7:27 pm
I'm wondering if I wired this thing correctly. Looking at the 1969 - 1970 A50 wiring diagram, it shows two wires off the stator, GY & WG. I have three wires: GY, WG and the third is Back/Green. Some one said I should just combine the BG wire with the GY wire... (confusing) is this right?

also, the manual says to test the stator by checking volts with a 1-ohm load resistor. I'll have to find one somewhere.

My battery came with the bike, looks old. I plan on replacing it, but I need to verify if the charging system is working,.
Posted By: chaterlea25 Re: A50 charging system question - 09/29/19 9:19 pm
Hi
I assume you change the meter setting to AC when checking the alternator output?
A moot point anyway since [quote] I connected each alternator wire to ohms meter, with other meter lead grounded to the frame. The meter read 1.0 ohms... so, what's next? [/quote
Assuming all the alternator wires disconnected from the loom?
This would indicate that the alternator coils are shorted to ground
There should be no connection between the wires and ground (chassis)
A quick and dirty test of the alternator output can be made with a 60Watt 12v headlamp bulb
It should light connected across the alternator wires but should not light with any wire and ground with the engine ticking over

John
Posted By: NickL Re: A50 charging system question - 09/29/19 10:30 pm
Combine the BG wire with the GY wire before connecting to the pod. (That's the earlier stator fitted.)
If those are not combined the alternator output will be very low.
There should be no connection between any alternator cable and frame.
The coils will read less than an ohm when measured normally.
As stated the stator (with it's wires appropriately linked) will light a headlamp bulb at a couple of thousand revs.
A good battery will show 12.6 volts or more after sitting unconnected for 12 hours.
Posted By: Allan G Re: A50 charging system question - 09/30/19 12:05 pm
Originally Posted by Danam
I'm wondering if I wired this thing correctly. Looking at the 1969 - 1970 A50 wiring diagram, it shows two wires off the stator, GY & WG. I have three wires: GY, WG and the third is Back/Green. Some one said I should just combine the BG wire with the GY wire... (confusing) is this right?




How are they linked now? if at all? the 3 wires are most likely the 6v alternator with emergency, if you check the poles on the stator it will confirm this 6 poles with 3 wires as just described, 9 poles with 3 wires is 3 phase, and a much better charging system.

If your only using 2 wires of a 6v alternator then the best it will give out is about 8v with no load (obviously much lower than the battery) I've linked them before and they work fine as 12v (like on bantams where you have no other choice) but on a large alternator like the A/B series bikes, change up to an RM21 (single phase 12v 120w output) or RM23 (single phase 12v 180w high output)
Posted By: KC in S.B. Re: A50 charging system question - 09/30/19 1:09 pm
Don't know if you are willing to take it apart to see what is in there. Certainly the most positive way to check out the situation as a Allan points out. The problem with these bikes is the Past owners sometimes have added parts that fit, but were not correct for the year etc. So it would answer how you could see a 6 volt alternator in a '69 bike. If you try the tests above, still have no luck, take it apart to look and find the part is not correct, I have some spares you can have for the shipping. I tested these out on the bench some time back, and they are stock parts, working as made.
Curious, what is the history on the bike,........ Did you just get it?
Posted By: KC in S.B. Re: A50 charging system question - 09/30/19 2:50 pm
Got me wondering how long ago that was. ".....I have some spares you can have for the shipping. I tested these out on the bench some time back, and they are stock parts, working as made. "
Looked and found these of the test rig, 2012. How time flies !!!

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Posted By: kommando Re: A50 charging system question - 09/30/19 4:16 pm
As Allan says the 6V alternator will operate as a 12V alternator but the output is limited in the larger engines are they are used at lower revs. In a Bantam being driven at max revs by a spotty 17 year old they work fine, in a 650 with high gearing and lights on it does not keep up.
Posted By: Danam Re: A50 charging system question - 09/30/19 4:40 pm
Thanks for the info, I will open it up and let you know what I see.
Posted By: quinten Re: A50 charging system question - 09/30/19 8:14 pm
the 6 pole 3 wire stator , wired externally to make it 2 wire ... 12 volt ready .
is shown on some BSA wiring diagrams through 1969 .

the early 2 wire , 12volt stator is the same stator in that it has the same output as the 3 wire .
all they did was make the same simple wire connection inside the stator encapsulation .

have you tried wiring the 3 wires as advised above ?

(green) black and yellow ... joined as one AC regulator input
(green) white wire left as the other AC regulator input .

its simpler and less messy to recheck the regulators AC input connections ...before opening the primary case .
those crazy voltage readings
were an indication of rectified output .
Posted By: chaterlea25 Re: A50 charging system question - 09/30/19 9:52 pm
Hi All
Repeating what I said earlier, If there is any ohm reading between any of the alternator wires and ground the stator has a fault

Quote
[quote] I connected each alternator wire to ohms meter, with other meter lead grounded to the frame. The meter read 1.0 ohms... so, what's next? [/quote


John
Posted By: NickL Re: A50 charging system question - 09/30/19 10:10 pm
Originally Posted by Allan Gill
Originally Posted by Danam
I'm wondering if I wired this thing correctly. Looking at the 1969 - 1970 A50 wiring diagram, it shows two wires off the stator, GY & WG. I have three wires: GY, WG and the third is Back/Green. Some one said I should just combine the BG wire with the GY wire... (confusing) is this right?




How are they linked now? if at all? the 3 wires are most likely the 6v alternator with emergency, if you check the poles on the stator it will confirm this 6 poles with 3 wires as just described, 9 poles with 3 wires is 3 phase, and a much better charging system.

If your only using 2 wires of a 6v alternator then the best it will give out is about 8v with no load (obviously much lower than the battery) I've linked them before and they work fine as 12v (like on bantams where you have no other choice) but on a large alternator like the A/B series bikes, change up to an RM21 (single phase 12v 120w output) or RM23 (single phase 12v 180w high output)



The 3 wire stator has the same output as the later 2 wire version. BUT you must connect the BG+GY together.
The RM21 is the same as the RM19 as far as power output is concerned. It's just a matter of how the connections are arranged.
As KC shows, the stator will give you around 100v AC quite easily with no shunt or load. It's not good practise to do this though
as the insulation voltage on those old stators is pretty low and once it's broken down anywhere it's life will be shorter.

Charterlea has repeated a very relevant question. (There should be no connection between any alternator cable and frame.)
Posted By: Danam Re: A50 charging system question - 10/12/19 5:54 pm
Hi, sorry for the long delay. Work and life prevented me from working on my BSA. Today I started checking all connections, and I noticed that when the ignition is switched to OFF, I still have a parasitic draw from the battery. This may (or may not) have something to do with my battery not charging, but I better fix that first! I found there is still power going to the coil on the red wire from the Boyer unit. This is also grounded, so it's draining the battery.

Please look at this sketch of my wiring. It is very basic (I didn't draw in the fuses so relax, they are there smile ) As the note states, I disconnected the white wire from the boyer to the switch and it still has a parasitic draw from the battery. I disconnected all the wires to the ignition switch and no change (just wanted to eliminate a faulty switch). Please let me know if you think I have this wired correctly, it looks correct to me after many hours looking at Boyer & Podtronics wiring diagrams. I'm wondering if my stator unit is supposed to have some resistance? Thanks for you help!

Here's my diagram
[img]https://drive.google.com/file/d/0B4rEJnCewvHDQXpKekstMVdFUFlXUC12LVpVS09VTEFjRWNN/view?usp=sharing[/img]
Posted By: quinten Re: A50 charging system question - 10/12/19 6:33 pm
Your wiring diagram shows the podtronics hooked up wrong . !!!

the red POD wire should go to ground... at or near battery positive ... for positive ground .

the black POD wire joins the negative circuit .... between the battery negative pole and the ignition switch .


the boyer looks to be wired correctly
Posted By: koan58 Re: A50 charging system question - 10/12/19 9:09 pm
I've seen that diagram before, some time ago.
The fault was pointed out then, it is as Quinten describes.
The +ve and -ve wires from the Pod are shorted when the ignition switch is on, so the Pod cannot charge the battery.
If lucky, the Pod may not have been damaged, but it will have been putting 12V through a direct short while running (and through the ignition switch), so assume nothing.

That you have the "parasitic draw" does suggest a possible breakdown within the Pod, but I'd say just rewire it correctly (ie Pod red to +ve) and see if it works ok.
Hopefully you will be lucky!
Posted By: NickL Re: A50 charging system question - 10/12/19 11:17 pm
That's a great diagram, green to brown and blue to bits eh?

You must have noticed when you drew it? (Lets just put a switch across the pod output and see what happens.............lol)

Try grounding the red pod wire and connecting the black pod wire to battery neg. and see how you go.
The black pod wire connected to where it is at present means the ignition switch will not switch a running engine off, the
pod will keep supplying power to the boyer and coil. So once started.....no stopping.

Most of those regulators are pretty bullet proof so you will probably get away with the cock-up.
Posted By: quinten Re: A50 charging system question - 10/13/19 1:16 am
There's something else wrong in the bikes ( real wiring ) or miscommunicated .
if the coil has a draw ( does the coil really have a draw ?)
... its not related to the POD mis- wiring shown .

if the white wire is open ( per red ink on drawing ) ... there is no the negative Supply to the
B-box ... and coil . .. no circuit potential .

correct wiring of a boyer
has the coil ... mostly off .(no voltage in the black wire between B-box and coil )
except briefly when turned on and off ... or if the timing stator is spinning .







Posted By: Danam Re: A50 charging system question - 10/13/19 5:35 am
Ok, point taken. I changed the wiring as suggested. I get no spark now. I guess I fried the podtronic. I’ll order a new one and let you know what happens. Thanks!
Posted By: Danam Re: A50 charging system question - 10/14/19 3:08 am
Ok! One last check and I found some bad connections. The changes you all suggested worked and now the bike starts up 1st kick and charges!!!!!! Thanks for all of your help here. Believe me I could not have figured this out without your help. Thanks guys!!!
Posted By: tg4360 Re: A50 charging system question - 10/14/19 1:13 pm
Did the phantom draw go away as well?

TG
Posted By: Danam Re: A50 charging system question - 10/14/19 10:50 pm
Yes! Swapping the wires at the Podtrionics fixed the charging issue and the parasitic draw. Also, now when I turn the key off, the engine stops. It did't before. I love fixes that don't cost money!
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