Topic: 750K not charging. Scratching my head...

[Bonz55]

Should that grounding test also work with the key on?

Works with the key off. Not with the key on.

(I got it to beep by the way following your instructions, only with key off)

[MetroRedneck]

Key off.  You may not be making good contact on the terminals when testing.  Getting the 12 volts is good.

Check continuity on the green wire that goes to the alternator.  One probe on battery ground and one probe on the green wire (maybe black as you near the alt) as close to the alternator as you can find a connector.  Use the beep function on the meter again.

Check continuity on the white wire the same way.  One probe on the bike harness white near the alternator (same spot as above) and the other probe on the bike harness at the regulator field coil connection (white wire in the bike harness where the regulator white plugs in).

If those both beep, then hook everything back up (main white connector), black wire to black bike wire, white wire to bike white wire, and retest the white with the red probe (just touch it to the connector inside the jacket with it plugged in) and black probe to the battery with the bike running. 

[Bonz55]

Thanks again. I did all those tests and it beeps in every scenario. I'm still only getting 12.3v on the battery with the bike running, no matter the RPM

[MetroRedneck]

What was the voltage at the white wire with the bike running?

[TwoTired]

Should that grounding test also work with the key on?

Works with the key off. Not with the key on.

You have a device not grounded properly, and it is "finding" a return path via another components power to true ground connection.  That's why you are getting 24v measurements.  Because light bulbs have such low resistance, it will take some skill and luck to find the error with an ohmmeter.  Really ought to be able to find the ground path error visually, by connections to a known good wire diagram.  Otherwise, create the condition/test set up where you measured 24v previously, then use the voltmeter to find 12v on a green power return connection.  (assuming you are still using Honda's color coding.). Place one voltmeter probe on the batt neg terminal, and probe the other batt return connection on each device that uses power.  Something is going to read 12v instead of near zero.  And that branch is where you have a wrong, or no, connection.  Then take the palm of your hand and smack your forehead as hard as you can.

Cheers,

[Bonz55]

Lol, thanks! I will try this.

Although I didn't think that would be the issue because the R/R was working fine, and all of a sudden stopped working. I hadn't changed anything in between those two scenarios, so something not being grounded seems strange to me.

[MetroRedneck]

Explanation on how it's possible to get a 24V measurement from anywhere in a 12 volt system with the bike not running, even with wiring issues?  I'm usually not the smartest guy in the room, but that's impossible, and I'm pretty sure that was an error using the meter, as are a few other results.

What is the reading at the white wire with the engine running with everything connected and the black probe on the battery negative and red probe on the white connection and the meter set to read DC volts?  Based on the other 1 by 1 testing, if it is less than high 11 volts, then likely your regulator is bad or your battery is bad.  Do you still have the old mechanical reg you can test with?  Leave the combined unit attached so you're using the rectifier portion, and then connect the old reg to the green/black/white wire pigtails on the bike.

[TwoTired]

All it takes is a capacitor, a diode, and a circuit breaking into oscillation to double the DC voltage.

All these could be present in an electronic reg, or elsewhere on the bike, particularly with interconnection issues.

Anyway, that's why I've been asking about the bikes wire diagram/ mods.
Can't analyze a circuit without proper data, OR, faulty data reporting.

I'll step out and let others proceed with guesswork. Got a long drive ahaed of me today.

Cheers,

[Bonz55]

I ordered a new regular just to be sure I didn't grab a bad one (was only $25 or so) and did your test again. I wanted to give you the results of the test you asked for with the new regulator.


Test 1, voltmeter red probe to battery positive, voltmeter black probe to BLACK wire off RR

Key off - 12.6v
key on - 397
Key on, bike running - .5

Test 2, voltmeter red probe to battery positive, voltmeter black probe to WHITE wire off RR

key off - 12.6v
key on - 12.4v
key on, bike running - 12.28v

So looks like the black wire from the NEW RR is funny. Still think something isn't grounded?

[Bonz55]

The only other things I can think of are....

I changed my 15A fuse to a larger cylinder. I didn't think it would matter since it's 15A but figured I would bring it up (photo attached)

My electric starter also has a bit of wear on the two wires leaving it.... I believe one goes to the 15A main fuse. (Photo attached).

[b52bombardier1]

Your key on numbers of "397" are odd. And the bike running with ".5", also odd. I see around 14.3 vdc with the engine running at moderate speeds and all lighting on.

You never mention any AC measurement at the battery with the bike running.  It takes a good meter to measure small amounts of AC accurately but it's always a good check on the health of the rectifier diodes.

Rick

Sent from my SAMSUNG-SM-N900A using Tapatalk

[TwoTired]

I changed my 15A fuse to a larger cylinder. I didn't think it would matter since it's 15A but figured I would bring it up (photo attached)

Not part of the charging issue, but it does matter.  The longer fuse forces less contact area.  Expect it to heat up and melt the plastic holder in the future, ans well as melt under the end caps, under normal running currents.

[Bonz55]

I changed my 15A fuse to a larger cylinder. I didn't think it would matter since it's 15A but figured I would bring it up (photo attached)

Not part of the charging issue, but it does matter.  The longer fuse forces less contact area.  Expect it to heat up and melt the plastic holder in the future, ans well as melt under the end caps, under normal running currents.

Okie doke, thanks!

Any thoughts on my readings? Still think something isn't grousing?

If so, could you possibly explain how to check for that? I read your example above and don't understand 100%.

My level of knowledge from 1-10 is maybe a 3 on a good day

[scottly]

The job of the regulator is to control power to the field electromagnet. When 12V is fed to the field coil, via the white wire output of the regulator, it produces a strong magnetic field that can be checked very simply with some bolts; with the key on, bolts should stick to the 3 screws on the alternator cover. If they don't, you have a regulator or field coil problem. With the black meter lead connected to battery -, and the red meter lead connected to the white reg wire, you should read 12V with the key on. If not, and there is 12v at the black reg wire, the reg is at fault. (All measurements are with the wires connected to the reg.)
Some of the cheap reg/rects may need to have the metal body grounded with an added wire from the body to a good frame ground, while higher priced units may not.

[Spanner 1]

The Green wire from the rect/reg. unit MUST be grounded to the frame or battery -. Just 'cos its Green color coming out of the R/R does NOT mean it's at ground potential, no, it it's a Green wire that means it NEEDS TO BE GROUNDED. Same with the Green from the alternator, make sure it goes to an actual Ground, not any presumed or airyfairy ground, do it and... good luck.  First advised that ^ 15 days ago BTW. 

[Bonz55]

The Green wire from the rect/reg. unit MUST be grounded to the frame or battery -. Just 'cos its Green color coming out of the R/R does NOT mean it's at ground potential, no, it it's a Green wire that means it NEEDS TO BE GROUNDED. Same with the Green from the alternator, make sure it goes to an actual Ground, not any presumed or airyfairy ground, do it and... good luck.  First advised that ^ 15 days ago BTW. 

Hey, thanks again. I remember you advising that. I think someone replied to you and said that it should be grounded via the harness plug and I double checked that it was. I'm on an airplane and looking st an iPhone SE screen which if you know anything about iPhone's is approx the size of a finger nail so I'll verify again tomorrow.

Thanks.

[Bonz55]

The job of the regulator is to control power to the field electromagnet. When 12V is fed to the field coil, via the white wire output of the regulator, it produces a strong magnetic field that can be checked very simply with some bolts; with the key on, bolts should stick to the 3 screws on the alternator cover. If they don't, you have a regulator or field coil problem. With the black meter lead connected to battery -, and the red meter lead connected to the white reg wire, you should read 12V with the key on. If not, and there is 12v at the black reg wire, the reg is at fault. (All measurements are with the wires connected to the reg.)
Some of the cheap reg/rects may need to have the metal body grounded with an added wire from the body to a good frame ground, while higher priced units may not.

Key on... bolts do not stick.

With black meter lead to battery negative and red meter lead to white reg wire..... I get something in the 30s. bounces between 27-30vs. I know that doesn't make sense but I'm not sure what to make of it.

There is approx 12v at the black wire leading from reg/rect with key on.

Anyway to tell if it's the regulator at fault vs. a grounding issue?