Topic: CB 550k charging issues battery choice?

[Xdeano]

So ive got a 1978 CB550.
I bought the bike with a Etx15 battery. Ive charged it completely and it looses charge very quick so I figured it had a bad cell, so I run up to the bike shop to get a battery. I tell him what ive got and he said that my issue is that the bike should have a xt12aa instead of the 15. He said that the bike wont make enough charge to charge the battery. So I went to batteries plus because the bike shop didnt have one in stock. Batteries plus gives me a Duracell 15. Same size as the battery that was in the machine.

So should I go back and get the 12aa? Whats true and what's a bunch of crap? I'm asking you guys for some help.

Thanks
Deano

[calj737]

The first is a bunch of crap. What is true is you appear to have a charging issue with your bike. Have you done any diagnostics to determine the actual cause?

[Xdeano]

Ive tested the stator, regulator and rectifier. All seem to be working just fine. The bike doesnt have anything besides the running system. The light has a manual shutoff and I dont have blinkers so there shouldnt me much of a draw besides maybe a brake light.

Deano

[scottly]

What voltage do you measure across the battery terminals with the engine running at various RPMs?

[Xdeano]

I can get that to you tomorrow. Its getting late for tonight.
The wife would loose it on me if I went out and started it up. Hahaha

Deano

[scottly]

Make sure the battery is charged before the test, or at least note the battery voltage before starting the test.

[Xdeano]

Ok fresh brand new battery 12.95v hooked up but switch not turned on.
At start idle 12.38v
Rev 12.40v
Ran down the road a half mile and back and I was down to 12.31v
Turned off it goes to 12.67v
Front light was off
Only tail light was on. Regardless this should be charging the battery.
Ive checked the stator and it reads correctly. Checked the rectifier and it reads correctly. The regulator doesnt do anything only the white and green wire hooked up, the black doesnt go to the ignition because there is no ignition. I kick start. I am at a loss.
Deano

[scottly]

the black doesnt go to the ignition because there is no ignition. I kick start. I am at a loss.
Deano

You need to provide 12V to the regulator black terminal in order for the charging system to work. How are you switching power to the coils? The reg black should be fed by the same switched 12v source as the coils.

[Xdeano]

So I bought this bike from a guy and its Jerry rigged from hell. What I should do is completely rewire the whole damn thing. I'm so irritated with the wiring I could take my 375 cheytac and a can of gas after it.

So hes got two switches wired in as electrical on/off.  There was a red wire that was attached to the regulator and it was carrying the same charge as the battery when switched on. It was attached where the black wire should be but as soon as you flip the on switch the wire smokes off. Crispy. Ive replaced it twice.

So I need to get that black wire that is hot to go back on the regulator terminal. Maybe the regulator is bad. Or maybe its in reverse. Its obviously shorting out and burning up.

Deano

[scottly]

You can attach pics directly using the Attachments and other options button; just try to keep the resolution down to a reasonable 1 or 2 meg.

[Xdeano]

I may have just stumbled into my charging issue. The guy who I bought the bike had the ground hooked to the hot side of the regulator, and black hooked to the ground which was hot. In the process of figuring out what was wrong I fixed a Jerry rigged 3 way connection and made it live again which was my hot lead down to the regulator. Not knowing I flipped the switch and the hot wire burned up. I changed it out and didnt reconnect it to the regulator figuring it would do it again. Bike ran fine but I still wasn't getting a charge to the battery, so no change in charge to the battery.

 I just thought of it this morning after looking at the wiring diagram and a photo of the regulator I pulled up on eBay.  My regulator didnt have a sticker diagram for attaching the leads. After looking at the picture it dawned on me that My green and black were switched around causing the short, and before that the connection that wasnt tied in correctly.  I went out and fixed it quick, flipped on my power switch and nothing got hot. Ill take it for a spin after the kids get up.

Deano

[Xdeano]

Here is my regulator without the sticker...
Deano

[Xdeano]

So here are my voltage numbers off the terminals.
Fresh battery charged up 12.94v.
Power switch on 12.40v.
Started and at idle 12.51v.
Revved up a bit 13.51v
I ran it down the road a mile and stopped at idle 13.38v
Off 13.06v

So everything is charging now.

I appreciate the help guys.
Deano