Topic: 'flat part' on starter... oops, maybe it's the charging system!

[Frankenkit]

Is there any possibility it could just be the battery?  I had it on a trickle charger all night, was at 100% this AM, disconnected it just long enough to test the fitment of the new battery lug, connected it again and it went from red to 'flasging green' which supposedly means it's around 80%.  It's a newish battery, but sat at low charge fow a long time...

going back out to clean more connections...

[martino1972]

i would also double check the multimeter by measuring a car battery or something to see how accurate the meter is..
ive seen multimeters that where off a few volt's,telling you its 15 volts on battery could as well be 12.5/13.4
just hook it up to a runnig car and see what she puts out then,if it reads 15 also,then your meter  is off..

[paulages]

someone else can probably describe the test better for you (probably TT), but you can do a load test once the battery is fully charged to determine if it's damaged. turn the headlight on and leave it on for 10 minutes. a good battery should be able to do this without severe depletion.

[TwoTired]

Is there any possibility it could just be the battery?  I had it on a trickle charger all night, was at 100% this AM, disconnected it just long enough to test the fitment of the new battery lug, connected it again and it went from red to 'flasging green' which supposedly means it's around 80%.  It's a newish battery, but sat at low charge fow a long time...

going back out to clean more connections...

Yes, it could easily be a battery issue, that may well have been damaged by overcharging when full, or sitting uncharged for long durations, or both.  You have a meter.  Use it!  Just remove your jewelery before probing active circuits.  The bike won't hurt you. Their isn't enough voltage, so you won't even feel a shock if you put your hand on the energized circuits.  If you still feel wary, use some dish-washing gloves while probing, tight ones are better.  You can't break a broken bike!

After your charger says it is full.  Disconnect the charger and let the battery "normalize" for two hours unconnected.  It should not fall below 12.6 V, and is suspect if it does.

Don't let the battery charger outsmart you.  If it is an automatic type, it will charge the battery to 14.5 V and then switch to trickle mode to keep it above 12.6V.  It should maintain the battery at a slight surcharge to keep sulfation at bay, slightly agitating the internal chemicals.  If you disconnect the charger, it loses it's prior "knowledge" about the battery.  A battery with voltage below its "maintain" state may only be assessed an 80% ranking until the charger gets it back to the 14.5V peak in recognizes as "100%".
There are hundreds of different battery chargers and charger types available.  So, this is a bit of generalization, since I haven't a clue as to which charger you have.
The wait period for testing after charging is to allow the chemicals to stabilize from external agitation input.

Batteries will self discharge all on their own over time.  When they get to a low enough state, the chemical convert and form an insulative coating on the plates.  Which diminishes its capacity for output.  Recharging can reconvert some of the sulfation, provided it has not progressed too far.  This is exactly what a battery maintainer is intended to prevent.  But, it has to be connected for it to be effective.  I don't know of many wireless battery chargers, in common use.

I'm getting a bit frustrated here.  If you would prefer to just keep replacing parts on the bike till it works again, that is an alternate method to the "test and evaluate and replace only what is needed" approach.  It could be more expensive though, unless you get "lucky".

Good luck!

[Frankenkit]

OK, probing the white and black wires to the alternator, my result was 96.3.

Testing constant drain, on a link directly from lug to battery terminal was -61.6 with key on, 0.00 with key off.

On R/R again, leads were 96.8 while connected and 96 while not.  This is on the 'male' connectors, on the 'female' it was always '0.00' no matter what.

Not sure if it's related or not, but testing the R/R, I popped my main fuse. I don't have a spare, so I'll have to pick one up tonight or tomorrow after work.  I don't have a spare b/c while the bike was in the shop, somehow it blew one there, too.

edit:
managed to catch a nasty stomach virus so work on the bike will have to wait until I'm able to handle it.

[TwoTired]

OK, probing the white and black wires to the alternator, my result was 96.3.

The rotor should measure 6.8 ohms, give or take 1 ohm.  When they fail they usually go much lower.
However, if the brushes are worn, the reading can easily go higher.  If you trust what you've measured as accurate, then it's time to gain access to the brushes in the alternator.
I have doubts at the validity of your measurement, however.  And, I hate to direct further action, until I have confidence that what your are reporting is truly representative of your equipment.

Testing constant drain, on a link directly from lug to battery terminal was -61.6 with key on, 0.00 with key off.

On R/R again, leads were 96.8 while connected and 96 while not.  This is on the 'male' connectors, on the 'female' it was always '0.00' no matter what.

I would expect a bike drain of about 10 amps on the battery with the Key On.  Since your reading is so different, from what is expected, I have to suspect some kind of testing error.
I think you may have to also tell me details of how you're meter leads were configured, what settings you used for the function knob, and exactly where your meter probes were placed for the test reading.

No offense meant, but the numbers given so far, don't give me data I can use to guide to the next step.  Either something is very odd with your bike, or the reported numbers are inaccurate.

We may have to begin your training on a DMM with simpler voltage measurements of the battery(s).    A DMM is kinda like a Swiss Army Knife with a hundred tools to select among.  If you select the wrong one or use it improperly, you don't get very helpful results.

Get well.   And, let us know when you feel confident to resume circuit testing and analysis.

Cheers,

[Frankenkit]

Yeah... I was also kind of waiting on my friend b/c I don't really know how to use a multimeter, much less really read one right.  Hopefully tomorrow or the next day...

[Frankenkit]

ok, so I got 102 ohms resistance at the rotor,

 2.2M ohms @ the R/R connected, and 1.9 M ohms completely disconnected from the bike wiring.

Testing drain, I got 7.55 amps  with the bike 'on' and basically nothing off. 

What does this all mean?

[TwoTired]

Your alternator should have 5 wires going to it; three yellows, a White and a Black (according to the Clymer diagram I referenced).
The white and black are the rotor windings and they connect via "slip Rings". 102 ohms resistance means the alternator cannot make very much power out those yellow out put wires.
If these White and Black wires truly measure 102 ohms, then this is definitely a problem, as they should read about 6.8 ohms. 

Verify the rotor resistance is 102 ohms even after you turn the crankshaft.  If it persists, then you have to get to the slip ring brushes, and measure the rotor resistance at the slip rings themselves.  It may be that the slip rings have formed a glaze that is preventing good contact or the brushes may simply need to be replaced.

2.2M ohms @ the R/R connected, and 1.9 M ohms completely disconnected from the bike wiring.

I don't know much about the meaning of this.  You will have to be more specific about what terminals you are measuring and what setting the meter settings were.   And, I have no internal schematic of the R/R or and example to characterize what resistance it ought to read.  Further, there are transistors inside that behave differently when voltage is applied to them.
After getting the question of the rotor resolved, we will make voltage measurements to see how the regulator behaves in operation.

Testing drain, I got 7.55 amps  with the bike 'on' and basically nothing off. 

This I would interpret as good news.  It is an indication that the rectifier portion of the R/R is behaving normally.  And, that your suspicion of constant drain on the battery while sitting at rest is unfounded.

However, with the alternator rotor misbehaving, it would explain why your battery does a constant drain while in operation, as your battery isn't getting recharged.

Another test you can do is a voltage test of the battery while the engine is running.  Measure the Battery voltage at 1000, 2000, 3000, 4000, and 5000 RPM.  This test is best done with a battery known to be a full charge before the test.

Cheers,

[Frankenkit]

For the R/R, I was testing the female connectors on the black and white wires you'd referenced.  That seemed like an awful lot of resistance, so I wasn't sure.

When it comes to turning the crank shaft, should I just wheel the bike back a bit, or should I actually start it?  The battery is at 12.55v right now.

I'm doing my best without my clymer book- I seem to have lost it somewhere in transition.  Is there anything I should specifically look out for when I attempt to access the slip rings, and is this a matter of just taking off the alternator cover?  The parts fiche doesn't provide a lot of detail.  Thanks again!

[TwoTired]

 You'll have to remember, I know how the electrical is supposed to work.  But, I don't have intimate knowledge about the physical arrangement on your bike.
I don't have a 650, only admired them from afar. 
Therefore, I don't know if the female connectors you refer to, belong to the alternator or R/R side of the connection between them.  The Clymer wire diagram gives me no such information.

It is too soon to worry about a 2.2M ohm or 1.9M ohm measurement of the R/R.  Because of the way an electronic R/R works, measuring the R/R with a simple resistance measuring device requires more skill and technique.  Further, since I don't have abase numbers to compare from a known good one, and don't have and internal schematic of the device.  All the numbers you've given so far say is that it is NOT definately bad, or a sure source of a charging problem.

The rotor, on the other hand, has reported numbers that are a clear indication of a problem.

Turning the crank for a rotor reading...
As a vereification of a former measurement, I'd do both.  Bump it with the wheel to see if you simply have a bad spot on the slip rings.  And, then run it to see what it reads in an operational state.  It is possible, that running it may get enough friction to scrape through the glaze.  If you do run the bike to measure the rotor, completely disconnect the R/R from the bike for the test, as a precaution to save it from further damage.
But, honestly, if it were my bike, and I measured a reading such as you reported, I would dismantle enough to physically lay hands (and probes) on the brushes and slip rings.

My unfamiliarity with your specific machine configuration prevents my detailed alternator access procedure.  Perhaps other forum members can provide info, if Clymer is unavailable.  I can only direct WHAT must be done.
I haven't looked.  Aren't there Honda Shop manuals for your bike available in the manuals FAQ?  I'd rather have that than the Clymer, anyway.

Cheers,

[martino1972]

i got 2 cb650's both from 1980,my bobber 650 im riding,but the other one i can double check the readings,just tell me excacly what wires your measuring (picture speaks a thousand words)and i will compair that with mine.....

[Frankenkit]

going to go out in a few mins. for pics, but by the time i get pictures and find the cable to upload them, and modify their size, etc...  I think this might help (pics will come, asap)

By the R/R, there are two connectors, a large one on top with two banks of 3 wires: the black wire, a space, then the white wire, and in the bank of 3 next to that, a row of three yellow AC wires.

Beneath that one is another connector with a thick green, a space, and a thick red.  I haven't paid as much attention to that one, so there are probably others but, as I said, I haven't paid as much attention. 

I've been testing the male leads for the black and white, the ones that lead to the rotor... 
For the R/R, I tested the female ends of the black and white connectors, which lead right to the R/R.

Here's the shop manual, it's for a '79, so slightly different, but the only diff. I've noticed inasmuch as the electrics are concerned is the color difference Paul mentioned with green and black leads off the R/R vs. my green and red. (obviously one is juice and one is ground)

[TwoTired]

Well, crap. Your connector description doesn't match the wire diagram I've been using.

I select the CB650C button from here:
http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php#class

This diagram shows 8 wire connections to the R/R.  Your description only describes 7.

In question is a second black wire.

I'm at a loss...

[Frankenkit]

Sorry, no, that diagram's right on, that's what I've been using as well...  I just forgot about the black wire that's beside the green and red.

[TwoTired]

Ah, well, that's a better picture on this world then.

Still, if the white and black wires leading to your rotor aren't reading near 7 ohms, the investigation leads in that direction.

You have to isolate wire issues, brush issues, slip ring issues, or rotor winding issues.

As a check on your meter manipulation capability.  If you measure a 50W headlight filament (disconnected), it ought to measure about 3.3 ohms.  This test is optional, only to gain confidence in your testing ability.
(If you were here, I'd give you assorted resistors to measure.)

Cheers,

[martino1972]

oke,i will take pictures,and show you to see if we are talking about the same thing...

[Frankenkit]

There it is... with the black _ white then 3 yellow AC wires... then beneath, green, red-and-white, and black.

[TwoTired]

Nice t actually "see" what we're tlaking about.  Makes perfect sense.  The upper connector on the R/R contains all the wires going to/from the alternator itself. The lower has the wire to the rest of the bike.

Is the dark part on that upper connector just dirt?  Or, is the plastic discolored from charring?    Are the internal contacts of BOTH connector halves bright and shinny?  Check those lower plug contacts, too.

Assuming dirt, you now have to get to the other end of those upper white and black wires on the left side of the motor.

Cheers,

[Frankenkit]

It's just dirt.  I pulled both apart and cleaned them until nice and shiny... though they weren't all that bad in the first place.

So, when I take the alternator cover off, I'm just going to throw out a dumb question and say "Will there be oil under there?"  I had purchased a full gasket set, and will replace that one after I open it (obviously) but wanted to know before I crack it, just so I don't make a mess in the carport.

[TwoTired]

Jeez, I would hope there is no oil in there, beyond maybe a couple drips.  Hard to imagine slip rings bathed in oil would work properly.
But, then again, SOMETHINGS wrong inside.  Perhaps it's best to be prepared?

Cheers,

[martino1972]

oke,i took off the top connector,with the black,white and yellow wires..
i measured between the black and the white and came up with this..



let me know what other values you need/want,and ill measure them including pictures to prevent mixups..
its long weekend here,and enjoy doing this,so dont be afraid to ask...
just dont ask me to take the pistons out..

[TwoTired]

Assuming you are measuring 50 ohms, I have to ask if your alternator is working??

And if so, why?

That reading doesn't match what other 650 owners have reported.  But, dirty slip rings could explain it.

Cheers,

[martino1972]

let me check my other cb650,see what that one says,its running and charging good..
this one i just bought ,seems to work fine,but not sure.....so ill take my cb650 bobber,be back in 2 minutes..

[martino1972]

oke,well,interesting,maybe i got the same problem then..

went to my bobber 650 and measured between the black and white wire on the top connector..
came up with 13.9 ohm...

and like i said,the bobber is running/charging good....