Voltmeter readings - Charging problem or not?

[J_C]

Hi folks. I decided to split this out into its own thread in case anyone was trying to find info in the future. I was mixing too many different analytics in one thread; must be overexcited \\/

Testing Charging system: Battery - New YUASA YTX14AHL-BS

Off - 12.8

Ign On - 12.34

Idle (1200 w/ choke) - 13.8

2500 - 13.25

4000 - 13.3

Oops, I completely forgot about following up on this until I was reading my clymer last night and it said that correct charging should be around 14.5 volt @ 4000rpms...

Is this discrepancy worth following up using the stator papers fault finding chart, or will this still charge correctly since this is a 12v battery, albeit less effectively? Has anyone seen symptoms similar to these (meaning is something on the way out?)? It seems odd to me that it was 13.8 at idle but dropped below the 13.5 spec for both 2500 and 4000 rpm tests.

[SqDancerLynn1]

It does need further checking First make sure to add a heavy ground wire between the (-) battery & the mounting bolt of the reg

[J_C]

Thanks for the reply. Crud. Looks like I have some reading to do. Electrical items have always confused the hell out of me.

[UncleMike]

It does need further checking First make sure to add a heavy ground wire between the (-) battery & the mounting bolt of the reg

So, we're not talking about using any of the connections coming off the R/R, just adding a wire from the mounting bolt to the neg terminal of the battery?

[beby99]

So, we're not talking about using any of the connections coming off the R/R, just adding a wire from the mounting bolt to the neg terminal of the battery?

Correct...unless you have a Honda R/R, than you use the ground wire from that to the neg terminal of battery. Actually... you could do both for added protection.

[UncleMike]

Correct...unless you have a Honda R/R, than you use the ground wire from that to the neg terminal of battery. Actually... you could do both for added protection.

I've got one, that I think is from a CX500. Would this be better to use?

[beby99]

I've got one, that I think is from a CX500. Would this be better to use?

CX500 is a Honda so yes its ok...I got a CX R/R on mine as well....works good.

[UncleMike]

CX500 is a Honda so yes its ok...I got a CX R/R on mine as well....works good.

Was nervous as to whether or not it would be better than a OEM R/R, and whether or not it would be adequate for the 750.

[J_C]

Whats the point of this ground? Was it not originally there?

The stator papers need more pictures :-D

[Steve]

Yes, there was originally a ground there, but it could be like mine. :-(

I was having charging problems on my 850 last summer. Checked stator, all good readings. Installed a new sealed battery, no improvement. Replaced the R/R with no improvement. Brought the bike home in a truck. Checking things closer at home, I found that the ground wire that connected the battery and frame to the mounting panel for the R/R and fuse panel was broken. Evidently this helped cause my problems with charging AND blowing the ignitor.

I replaced the ground wire and charging is great now, and I have a replacement ignitor on the way, so hopefully the bike will be ready for the body parts that will be coming back from the paint shop in a couple of weeks. :-)

[UncleMike]

Any chance we can get a pic or a real detail description as to where to mount this ground wire on the R/R panel? Go ahead and treat me like a dummy.

[J_C]

Oh.. I think I have this wire! Duh. It's a black wire coming from somewhere in the harness and screwed on to the right mounting bolt of the R/R. Is this right?

Is there something that should be done to test this?

[J_C]

disregard that... it's just the ground coming out of the rectifier. I see that now in the wiring diagram. I'm back to being confused with Mike

[J_C]

Are these three issues related?!?

First, I still have the weird readings I took with the charging system last week:

Testing Charging system: Battery - New YUASA YTX14AHL-BS

Off - 12.8

Ign On - 12.34

Idle (1200 w/ choke) - 13.8

2500 - 13.25

4000 - 13.3

Secondly, I identified a parasitic draw, around 1.1v that I isolated as originating between the connector before the R/R and the three wires after the R/R 8-[ Two of the three wires appear burnt or have melted shrink tubing.


Third The 10A "Signal" Fuse is blowing within a minute of being put in the fusebox. The previous owner decided to say to hell with it and put foil there as a bypass.


Unfortunately I can't do much more in the way of testing via stator papers right now since the bike isn't running right now (I can't test stator at 5000 rpms for example). Does anyone have any insight here? I know this is a bastard topic that is asked on a daily basis, so I apologize in advance

[duaneage]

There are three wires from the stator, all a shade of yellow with a stripe on them. Set your voltmeter to read low ohms, like x1. Unplug the three wires from the regulator for this test. The bike should not be started.

Touch the voltmeter leads together, and you might see a small value, like .6 ohms or something close. This is really 0 but the volt meter is reading the resistance of the leads.

Now measure from any two of the yellows coming out of the stator. Measure one pair, then measure the other lead to either of the first two.

you should see a small resistance, around .8 ohms.

Now, remember the value you got when you tocuhed the leads together? subtract that amount from whatever the stator wires read. If it is over 1 ohm the stator is toast. So if you get .6 with the leads together and 1.9 on the stator wires you need a new stator. IF you got 1.4 then it should be oK. If you get .9 ohms then it is also bad since it is shorted.

THe stator is a coil of wire and as such it has resistance. Too high or too low and it is not any good. It won't generate enough to charge the battery and run the bike.

From what you described and the burnt wires I think your stator is probably toasty. But check it before buying another. And look for
Honda Regulator Mod with the search feature to learn how easy it si to prevent this in the future.