CB77 Battery voltage dropping before my eyes...

Jlovvorn · Post by **Jlovvorn** » Sat Jan 14, 2012 2:36 pm

Took bike for first ride, all was well. Headlight was not connected.

Connected headlight, and went to start, and bike dead. Tail light very dim.

Meter says only 6 volts with key turned to on.

Disconnected headlight, still 6.

Disconnected horn, starter and all other wires to lights etc in headlight cup.

Charged battery to 12 volts.

Turned key to on, and watched the needle draw down to 6 volts in less than 1min.

What is going on? The bike ran fine yesterday.

There is nothing left connected except the coils and the starter, right?

Could the starter be shorted?

What kind of short would draw down the volts that hard, but not blow the fuse?

Every problem I fix, I pick up two more....

Jlovvorn · Post by **Jlovvorn** » Sat Jan 14, 2012 3:49 pm

Problem solved.

Bad aftermarket rectifier.

Put new one in this morning. That's when chaos started.

Pulled new, put old back in, and the bike is off an running.

Meter shows no resistance between first and second tabs on aftermarket.

Didn't know a rectifier could be bad right out of the box, and from a respected seller.

PM if you have a recommendation for a good replacement source.

brewsky · Post by **brewsky** » Sat Jan 14, 2012 4:21 pm

#276-1185 from radio shack...$3.49

Jlovvorn · Post by **Jlovvorn** » Sat Jan 14, 2012 5:17 pm

Wow, thanks. Just found the thread on that. Crazy.

brewsky · Post by **brewsky** » Sat Jan 14, 2012 10:23 pm

Your welcome

Jlovvorn · Post by **Jlovvorn** » Fri Jan 20, 2012 4:16 pm

This was not the rectifier.

The problem, according to the Silver book, is that some of the headlight dimmer switches on these bikes are set up so that the middle position is not a "super charge" but a both hi and low beam "on" position which will drain the battery in short order.

This problem has arisen for me a couple times, but now that I make sure the left dimmer switch is never in the middle, it has gone away.

Jlovvorn · Post by **Jlovvorn** » Sun Jan 22, 2012 4:48 pm

Well, its back.

it's not the headlight switch, and not the rectifier. Have looked for shorts (loose, frayed wires), but a short should blow the fuse, this is a load that draws down the battery in about 2-3 mins.

The bike runs fine, if you can get is started fast and before it drains down. Runs without stalling.

The battery is a month old. Could it be bad?

What kind of load on the system should be on the battery with the switch turned but nothing else on? As far as I can see, only the tail running light is on at that point, and it shouldn't eat a battery that fast.

Any ideas? Totally stumped...