new battery or something more serious

Thanks Rooster

Sorry, it's a replacement Rectifier/Regulator, and I've just installed it because when I did some tests on mine from Hayne's it was nowhere near!
I've inquired about a rotor, but need to make sure which I need - maybe the stator also!?

After I installed the replacement rectifier, I got up to 13+v reading when RPM up past 2000+ (on the 5-pin connector, negative to black, and positive to brown, positive to green gives something lower) Took machine out for short run (battery was at 12.4v and didn't put light on) when returned battery was still at 12.4v, so put it on trickle charge, and at the moment it's at 13.6v (reading on the charger)

I've dug out Dwayne Verhey's CD, and done some tests off that.
Ohms tests on copper rings on front of rotor came out resistance is between 4 and 6 ohms. (says that the wiring to the brushes, or the brushes themselves are at fault)
The brushes look fine to me, both same length, and clean, but I can't get them off at the moment(?) I would have to pull all the wiring out to check that, but seems like I might have to.............? (perhaps the wiring might be compromised in some way, partially burnt, and shorting whatever because that is where the wiring is closest to the engine and unseen)

Just re-tested the 3 and 2 pin connectors for the stator and rotor, made sure good connections and set on the 200 ohms on the meter. Did this 3 times.

Results were the same each time:
3-pin connector (stator): 2.2 ohms
2-pin connector (rotor): 34.6 ohms...... You say it should be .46? (the ignition is OFF, by the way)

Same tests with ignition ON:
3-pin connector: 2.0
2-pin connector: 35.9 (or is that 3.59?) You say it should be 5-15 ohms anyway?

The battery is now 'fully charged' on the charger, reading 14.6v
The meter reading on the 20v scale, connected to the battery terminals is 12.52v

Hope this gives you some more scope with evaluating what still needs to be done?

Thanks for all your attention to date.......!

Regards.

 

Both of those are quite high. Try touching the two DMM leads together (200 ohm scale) to make sure you get a reading of .2 or less - try touching the same terminal at different spots and you should also get a reading of .2 or less. Subtract that reading from the values you get when probing separate terminals on the 3 pin connector.

That's an improvement over before so perhaps the bike shop diagnosed correctly. Make sure the battery is fully charged and then check directly across the battery and see what numbers you get when revving up to 3K or so.

 

Done some tests this morning, typed it all out, and then lost it because I wasn't signed in!
Going out for a 14 mile run now and will report back on return........

 

Tested from charged this morning (after replacement rectifier in place):
Battery with headlamp OFF idling = 12.3v.....at 3000rpm = 13.6v......at 6000rpm = 14.6v
" " " " " " " ON idling = 12.58v....at 3000rpm = 12.31v....at 6000rpm = 13.66v

Was at 12.4v when I set off for 7 mile run headlamp ON. When arrived at destination tested across battery terminals, and still at 12.4v
On return (7 miles again) with headlamp OFF, tested across the battery after turning off ignition and reading was 12.59v

My assumption is that when it is under load, with the 100w headlamp on, it merely maintains the original charge whilst driving over 2000rpm?
When driving at over 2000rpm without the 100w headlamp on, and under no other load, the battery is being somewhat recharged, if only 1.5v after 7 miles? Is this increase in charge what it should be, or should it increase the charge anyway whether under load or not?
It seems to me that it should charge more, even with the headlamp on.

My neighbour came across this afternoon, who is an ex-mechanic and he iterated that if the 'bike is almost 40 years old (which it is), then potentially the rotor and stator are both that age also, and won't perform the same as when they were new, and hence won't kick out a charge at the rate they used to? (so one or both might need replacing to get maximum output? He also said that while my original rectifier was not working properly, or at all, the only charge that would be going to the battery would be AC current, not DC?
I mentioned that I haven't been able to get the brush system off yet, but visually they are at the right length (12mm), and the spring loading is working fine on them.
I have cleaned the rings on the front of the rotor til no more black comes off, but have not had the stator and rotor wire out physically to inspect those.
As I said earlier Dwayne Verhey's CD points out that if a resistance of 4-6 ohms is apparent from the copper rota ring test, the brushes should be replaced?
Took readings again of the 3 and 2 point connectors from the stator and rotor:

3 pin: 2.0 ohms +/- 0.2
2 pin: 13 ohms +/- 0.2 - That is a big difference from the 35.9 (or 3.59 from yesterday)
(Rooster, I'm not quite sure what you mean about 'DD leads', but if you mean tapping the two meter leads together to make sure the digital reading is at zero, before taking readings then I've done that) Please explain, if not and excuse my ignorance!
Another point, I must have recharged the battery about 5 or 6 times over the past fortnight or so, possibly weakening it's charge (when fully charged) a tad?

Having said all this (and cross referencing my battery tests results this morning and after the ride) Dwayne Verhey's chart says that (headlamp disconnected, take fuse out?) rev engine up to 2500........higher than 13.5v..........rev up to 5000.......Lower than 14.8v.........CHARGING SYSTEM PERFECTLY OK! (sorry if the capitals mean shouting?) But if you compare my results with what Dwayne Verhey says...........?

Any observations or decuctions greatly appreciated!

Regards.

 

I think your 100w headlight is simply too much for the charging system. This merely my opinion with a little speculation but when the headlight is off your readings are normal. It's only when the headlight is on that you get lower than normal charging voltages. I'm sure more knowledgeable members will chime in and correct me

 

Len usually gets it right and this is what he says:

"HCP8570 Aftermarket modular headlight system HALOGEN BULB, rated at 80/100W output, for all models that use a modular (replaceable bulb) headlight system. I cannot tell you how much we urge you to NOT upgrade to this rating bulb....but for the "bigger is always better crowd" well, here it is. Don't be surprised if you melt your wiring, or catch your headlight housing on fire, or fry your computer-controlled dash if your electrical system isn't up to snuff, though. Or even if it is.........."

I would agree for the reasons he stated - the switches, wiring, etc were not designed for that wattage.

That said, the charging system should be good for about 19 amps, so I would guess that it could handle the headlight as long as the battery is in good shape.

 

Copy your obs. Chilt, but the headlamp is an oversize stock issue for this machine, and various members have iterated that (IN USA especially) the legal requirements is to have headlamp on at all times when riding, and the machine is designed to charge battery whilst running and headlamp on.
You have just reminded me tho' that there might be an adjustable voltage charger somewhere on this model?
Can anyone else confirm this please, or is this just myth?

Thanks for your input

Regards.

 

Just read your input Rooster, I can't remember upgrading the bulb, but I'll have a look at it and report back. If it is indeed a 100w Halogen or similar, I'll replace it with the stock issue and test again?
Cheers.

 

I feel like an idiot for missing this detail.
There's the problem allright (potentially).

 

There is no adjustment possible to the charging system (unless you want to bother with depotting the R/R and making internal component changes).

 

When new I'd agree. With a cleaned and deoxed wiring harness I'd agree.
Variables....such a PITA sometimes.

 

Had the headlamp shell apart, looked at bulb and it's a 100/80 P43 T UV
The bulb holder had melted down two sides, but still worked! Took me a couple of minutes to prise the bulb out tho' and get new one in.
Replaced it with the only one I've got which is an H4 60/55W.
This bulb is working fine.
Readings across charged battery (light OFF at 3000rpm - 13.6v)
Readings with light ON at 3000rpm - 12.36v
Will take out for a run, with light ON, take readings before and after. (to see if charge rate any better, than with previous bulb in?)
Does anyone know what rating the correct bulb is please, so I can search and get one? (I'm assuming it is NOT the HCP 8570 warned about earlier in this thread?)

Thank you all for your help.

Regards.

 

Just found out in Haynes that it's a Philips H4 12342/99 (55/60W), OR an Osram Bilux H4 64193
I've put an H4 60/55 in anyway, but will get one all the same and install that (says got 30% brighter beam)

Regards.

 

The 60 watt low beam should be fine. I run a stock bulb and 20W worth of auxiliary running lights without any charging problems.

It still seems that your charging voltage is low with the light on though. Are there any accessories on the bike that you may not know about? I ask because I found a faulty alarm once that was constantly drawing more current than it should, and the alarm was well-hidden so it took me weeks to figure out.
Have you made sure that your meter is reading true, or used another meter to test with?

 

14 volts 19 amps at 5000 rpm spec from manual


100 watt bulb is drawing 7 amps if everything in the wiring is good.

 

The only accessory that I added, about 3 years ago, was a rectangular spotlamp (100w), installed in parallel, across the battery, and properly fused and switched. Hardly ever used it, only in foggy conditions. This had been turned OFF in all my previous readings.
The side-stand cut-off switch has not worked in years - don't know if that would affect charging system..?

Just fitted new 55/60w Philips bulb to headlamp.

Measured voltage across battery with engine and light off - 12.1v

Took for 7 mile run at 2000+ most of the way, with light ON.

Measured across battery again at 7 miles, light OFF and engine OFF - 12.0v!

Rode back home with light ON, 7 miles again, turned off light and engine and measured across battery again - 11.31v

Started machine again, light ON, and 5000rpm - 11.76v

Light OFF, at 5000rpm - only 12.12v!

This does not seem to be charging the battery, even with replacement regulator fitted, and lower load bulb?
As I have observed before, the brushes visually are ok, and I've cleaned the rotor face rings clinically.

I haven't got meter that measures that high in amps, so I can't check by that process.

I'll check the meter batteries, because when I turn it ON, and set to 20v, -1 keeps appearing, until I click the two electrodes together to zero it.
Could there be a short, or bad earth somewhere, caused by worn wire insulator, and this is reducing either the running charge to the battery, or it's capacity to charge, whether the light is on, or off?

(Or could it be the alternator/rotor/stator? Worn, and not generating enough charge? They are, potentially 37 or 38 years old)

Also, the battery is about 5-6 years old, although it is a gel one, and should be good for 8-10 years so threads on the 'net say. It has always charged up ok to capacity. (about 12.3 to 12.7v)

Any further thoughts appreciated....
Regards.

 

no amp test is needed. when talking about brushes visually does not cut it when talking about mm measurments

5 0r 6 year old battery sounds more like the issue

the regulator changes ac voltage to dc voltage and limits the output voltage.

 

Measured both brushes 2 week's ago and both at required 12mm

 

Just sent for replacement stator and lead.
See if that improves things.
Battery recharged to 13.7v, and charger said it was 'fully charged' at this, after initially reading 14.7v, and then coming down to the 13.7 and stabilising at this reading.

 

Might be a good choice as the stator readings you have posted were never very good.

You can measure the current through the field coil (rotor) to make sure the wiring, brushes, and regulator are functioning properly. Maximum current should occur when the bike is not running - it may go just a bit higher running at idle as brush contact improves with the rotor spinning.



You could also check the charging current by removing the main fuse and inserting a meter there. It is a little bit risky with just one meter as they tend to be rated at 10 amps, but if you are careful it shouldn't be a problem. Note also that the main fuse is part of the charging system and if the fuse box has never been replaced the contact between the fuse and fuse holder can cause significant losses causing poor charge - note this usually causes excessive heating also. Here is a video of the charging system at work with a fully charged battery - it uses two meters to monitor charging current but note that the total of the two never goes over 10 amps.