Topic: Charging stuff?

[prsman23@hotmail.c]

I know there is a pretty kick butt FAQ on this, but I have a question anyway.
When I picked my bike up from the shop he said he had to charge the battery the night before. (the battery is two weeks old). Then it wouldn't start, and he had to jump it. He said it wasn't the charging system because the headlight was still working (don't really know what this means), and chalked it off to a bad battery. The problem is this is the third 'bad' battery i've had in a month, the one that came with the bike (less than a year old), an autozone battery (a week old), and now a nice battery from Sears (a diehard). My question is "Do I still not rule out the charging system", or should I look elsewhere?

[dusterdude]

check your acid(and i mean not the type you ingest) and see if there is any in the battery.i cant imagine 3 batteries,including the sears battery,going bad that fast

[SteveD CB500F]

1 bad battery is bad luck.  (I've had a brand new battery that was bad)

2 bad batteries is a coincidence

3 bad batteries is a conspiracy!

I'd start by looking at the current drain while running and battery voltage vs revs. It should charge at everything over 2000 rpm.

[csendker]

The charging system (at least on a CB550) should be putting out:

@1,000 RPM ~12v
@4,000 RPM ~14.5v

Also, a short somewhere in the wiring can suck a battery dead overnight.

[78 k550]

My 72 500 wasnt charging. So I cleaned up the points and it is charging.

[KB02]

1 bad battery is bad luck.
2 bad batteries is a coincidence
3 bad batteries is a conspiracy!

I'd start by looking at the current drain while running and battery voltage vs revs. It should charge at everything over 2000 rpm.

Yeah, Three in a month... something's not right there.

The charging system (at least on a CB550) should be putting out:

@1,000 RPM ~12v
@4,000 RPM ~14.5v

Also, a short somewhere in the wiring can suck a battery dead overnight.

The short would be my first guess (If the charging system is indeed working properly). Take the battery out of the bike and give it a full charge. Let it sit over night and check it in the morning. Recond your finding (as for voltage and amps) Then but the battery in the bike and, again, let it sit over night. Check and record your findings. If you have a bad short or connection, you should be able to find out this way.

Your charging system may just be running fine, but there's something wrong somewhere.

[csendker]

I had a similar problem, a short somewhere, I think.  I tried to track it down, but never found anything concrete.  So I resorted to plan B: a cutoff switch.  You can get one at Wal-mart for less than $10.  I mounted it below the battery with some angle straps from the local hardware store, and wired it into the ground line (new ground wires, which may have been it all along...the original was pretty bad).  I kill the switch every night.  Maybe it was a bad ground wire (or connection).  Maybe a short.  Maybe I wasn't riding enough to charge (lots or short runs).  I also use a mini-battery tender now.  Not the most eloquent of solutions, but I was desperate and the problem has since gone away.

[jdpas29]

it sounds like you indeed have a short.  are there any parts of your bike (lighting, firing, etc.) that have never worked properly?  if so, this may be the area of the short.  check  there first before going over the whole electrical system.

also... this may sound moronic, but when i first got a new battery for my bike, i thought it was a 6 volt system due to the size of the battery.  i just couldn't figure out why the charge i was putting on the battery was soooo weak.      then i flipped the charger over to 12V and VOILA!!!  i felt like a total moron.

make sure your battery and charger are not resting on the ground.  sit them up on boxes or chairs or something.

make sure your ignition switch is OFF.

some of these types of batteries, if they have a rough time early on with charging, they can reverse polarity.  i'm sure there are posts on here somewhere about what to do if the battery is reversing polarity.  if not, google it.  there are times when you have to reverse your leads to get a good charge.  crazy, i know, but i've heard it works.

[SteveD CB500F]

Ha!

Found the charging table at last!  It was beginning to bug me - I knew it was here somewhere.

Its for a 750 but the 550 won't be very different.

The "night riding" figure for 1000rpm should read -6.5 amps (I think)

http://sohc4.us/?q=node/62

[cb(r)]

I quess I am missing something.
 is the battery draining over night? 
OR
Is the battery being drained while you ride it?
OR
both?

either way clean battery cables and grounds first.  check for broken wires and good contact at connectors .  check ignition is actually working correctly at shut off.    then check points and condensor.  this is the easier simple stuff. 
if this stuff doesn't work just ship it to me and I will take that voodoo contraption off you hands  

[BobbyR]

If you have a short and old time trick is to take a 12V bulb and attach the one lead to the Negative side of the battery, and the other lead to the frame. If there is a short draining your battery it will most likely cause current to flow through the frame and the bulb will light. It is a trick we have been using on cars for years.  The other trick is finding the frigging short. 

[prsman23@hotmail.c]

I quess I am missing something.
 is the battery draining over night? 
OR
Is the battery being drained while you ride it?
OR
both?

either way clean battery cables and grounds first.  check for broken wires and good contact at connectors .  check ignition is actually working correctly at shut off.    then check points and condensor.  this is the easier simple stuff. 
if this stuff doesn't work just ship it to me and I will take that voodoo contraption off you hands  

It's draining over night. I haven't riden it but 40 miles since I got it back, so I can't say with any authority whether or not it drains while I ride.

[cb(r)]

well do like I said it will not hurt anything and it is good maintenance. after that I would try the light bulb trick as said earlier.  that should  keep you busy for a while.  especially if it is a short in the wiring.

[TwoTired]

It's draining over night. I haven't riden it but 40 miles since I got it back, so I can't say with any authority whether or not it drains while I ride.

How do you know?  Post the battery voltage figures.  Just after it has run,  before and after you try to start it, and with the engine reving to 3-4 thousand RPM.

You could have a starter problem.

You could also tell us what bike you have....  There is no information in your profile or your posts about just which model Vespa you are trying to fix.

[dusterdude]

vespa,hahahahahahaha

[scondon]

      I had a significant draw from my battery, even with the key in off position. Battery would drain in a matter of days. Turned out to be the old regulator. Put in a new one and problem went away.

      I am no electrical genius, but I watched as my buddy used a multimeter to check for draw from the batterry with key in "off" position. Pretty simple procedure. Then just start disconnecting things, one at a time, until source of drain is found.

   

[Dennis]

      I am no electrical genius, but I watched as my buddy used a multimeter to check for draw from the batterry with key in "off" position. Pretty simple procedure. Then just start disconnecting things, one at a time, until source of drain is found.

   

Same concept as the "light bulb trick", only you don't need to use a meter that way.   

[scondon]

Same concept as the "light bulb trick", only you don't need to use a meter that way.

Damn, thought I had read ALL the posts.

    I bought a parts bike last year and the best part of the deal was the "tester" light with alligator clips that I found under the seat. You don't get numbers with the thing, but you can test/set just about anything on the bike with it. CHEAP!

[Dennis]

    I bought a parts bike last year and the best part of the deal was the "tester" light with alligator clips that I found under the seat. ....... CHEAP!

 

Test lamps are great, especially when you learn some of the finer points.
Nothing like a good meter, but still a great tool.
I have analog meters and digital meters and I will not give up my test lights, all 5 of them!

[prsman23@hotmail.c]

Sorry bout now telling you guys what kind of bike I have, I sometimes forget that everyone else can't read minds...
It's a 1980 cb650 Thanks again for all the recommendations

[ElCheapo]

When checking any charging system a meter with an amp clamp is priceless. You HAVE to know what your amp out out is. I have seen many times where charging systems give proper voltage and just can not give the appropiate amperage needed for the system.