Topic: Dead '75 550 charging problem?

[marvsho17]

I picked this bike up about a week ago and I've had to push it home more than once.  Today I went for a ride, got to my destination about 15 miles away and parked the bike.  I came back to the bike about 3 hours later and went to hit the starter button but the starter would just hum a little.  The front light worked and the neutral light was bright just not enough juice to turn the bike over. A few days ago I left the light on at the gas station while I went in and paid and the bike wouldn't start then.  The battery is only about two weeks old and is good.  This is my first bike and I'm not sure what is wrong.  Bad alternator??  I've got a Clymer Honda service manual but thats the only thing I've got to go on, that and the archives here.  Any help?

[bryanj]

alternators never(OK 99.9% of the time) go wrong. Problems in order of most common
(10 bad connection somwhere
(2) bad regulator -usually cleanable and resetable
(3) bad rectifier--replace.

The only book that gives the proper method of cleaning and setting the regulator is the genuine Honda manual which needs to be the 500 four one with the 550 supplements

[dusterdude]

will it kickstart

[KB02]

Do you have a handy-dandy volt meter? If so, that would be the best way to track down the problem.

It IS possible that you have a bad battery. Even though it is new, sometime they are simply defective. Take it out of the bike and charge it up. Check the charge on it and let it sit over night. Test it in the morning to see if it is holding a charge. Its should be the same, or at least pretty darned close to wehat it was the night before. Then, do the same thing with the battery IN the bike (charging safely out of the bike of course). This will tell you if you haver any kind of battery drain in the system.

Next, you want to check the charging system on the bike. Start the bike let it idle. Check the voltage at the battery. It should read around the 11-13 volt mark at idle. Then increase the throttle to around 3000 RMP. The voltage should be going up to around 14 volts. If you're not seeing a rise in the voltage, then you know your bike is not charging the battery.

When my old Nighthawk did this, it turned out to be a bad magnito. It had lost it's magnetic charge and wasn't producing the voltage it needed to recharge the system. It could also be a bad regulator if this is the case.

[78 k550]

I had the same problem on mine. Was only pumping out 7.6 volts. Cleaned  (filled) the points and not a problem since.

Paul

[78_SaltLick]

i had a new battery put in mine, and it went dead within a few weeks. Cell dried up in the battery, couldnt be recharged. Went out and bought a maintenance free battery and a tender, i dont like being stuck along ways from my house....

[marvsho17]

Thanks for the quick responses fellas.  I'm going to pick up the battery tonight and charge it or just pick the damn bike up.  I'll be bringing my voltmeter to see whats the battery is doing.  Btw, the battery is a Batteries Plus battery.  Anyone know where I can pick up a genuine honda manual?  Is there one online?

[TwoTired]

Anyone know where I can pick up a genuine honda manual? Is there one online?

Look in the FAQ.
Cheers,

[bryanj]

I can do a scanned copy on CD with the genuine Honda plus all the supplements for $10 including airmail postage if you want. Email direct if you are interested

[marvsho17]

Okay, I got back to the bike today and checked the voltage before doing anything, about 10-11 volts.  I turned the key on and got nothing at first.  Then I checked some connections and the fuses to make sure they were all right.  I turned the key on again and I got a real dim light that would increase in brightness but still dim.  The bike would not start with the button nor did I hear the starter.  But I did manage to get it started w/ the kickstart. 
The voltage then dropped to about 7 volts and I had to keep the rpms up to keep it running.  The front light would increase in brightness and the volts would jump to around 11-14 with the increasing revs.  But the volts would dip down w/o the higher revs.  I decided to take the battery home and charge it and take a chance to ride it home tomorrow in the daylight and while its 70 degrees out .  Would anyone know what could be fried?  Only thing I can think of is when I bought the bike the battery was dead and the owner hooked up a battery charger to get it started.  I'm thinking he fried something by introducing such high volts to the battery.

[marvsho17]

-I brought up the whole po battery charger thing up because while it was on I checked to see if the turn signals worked and the bike died.  Turns out the 15 amp fuse under the seat burned out.

[78_SaltLick]

dam these bikes.......

[marvsho17]

Well I still have high hopes for this bike once I get this problem fixed.  With the purchase price of the bike and a new battery I'm only in 220 bucks. 

[KB02]

Okay, the fact that you got nothing, checked some connections and then got something makes mwe think you might have a connection problem somewhere. Here's my advice (now): First and foremost, check your ground strap (battery negetive cable) for connection and corrosion. More than once I have seen a bad ground cause all kinds of funky electrical issues when dealing with a corroded ground. Pull it off (if you can), check out both ends, clean it up if you can - replace it if you can't. Then chack things out. If the problem still persists, do the same thing with the Possitive side of the battery.

[marvsho17]

The battery is charging and has charged overnight so I'm going to take a chance and ride it back
home today.  Once I get it back home w/ my own tools I'm going to go through the electrausa flow
chart and hopefully pinpoint the problem.

[csendker]

I just bought a '75 550 this year - new to motorcycles.  I had a new battery put in, and it too died.  I checked the running voltage and it was 13-14 volts, so I assumed it was charging OK.  I read somewhere that if you show voltage between the negative terminal and the wire - with the key 'off' and wire disconnected, then it's probably a short somewhere; of course, I have no idea if it's true.  I checked all of the light bulbs (easy to do) - popped each one out with no change in the meter.  I know there's been some 'cutting & pasting' done on the wiring harness by the PO, no time to track it all down.  After having it die twice, I went with plan B - I bought a battery disconnect switch, tender charger & a new negative wire.  I mounted the disconnect switch discreetly below the battery, and turn it off whenever I stop. I plug in the tender charger each night.  Never had a problem again.  I guess I'll try to figure it all out this winter.

[marvsho17]

Well, I got it home and I've been riding the bike about 40 miles in the last week.  I cleaned up all the connections I could and cleaned up the negative battery cable post.  But the battery never charges up enough to start the bike with the electric start.  I've just been kick starting it all week and its been getting me places.  Other than the lights getting brighter while I rev it up, I'm not getting any other symptoms. 

[TwoTired]

What's the battery voltage when you can't start it with the electric start?

[marvsho17]

Usually around 12 volts.

[Zane]

If someone hooked up the battery to an external source (boost or charge) while it was still onboard, and without disconnecting the rectifier beforehand; there is an excellent chance one or more of the three silicon diodes in the rectifier have been destroyed.  I'll email you instructions on how to check your rectifier, if you're so inclined.  (Does that sound dirty?  Maybe a bit, eh?)

[marvsho17]

Thanks for the email.   And yes, while he was charging it he bumped up the current and I think his words were "this thing has started a peterbuilt before."

[TwoTired]

Making current available does not cause more of it to flow.  The resistance of the load determines the current that flows through DC circuits.

The rectifier diodes are sensitive to over voltage and polarity conditions.  As long as your external source connection is in the 12-16 volt range, no harm will come to the rectifier diodes.  Another correction to prior posting is that you have SIX diodes in your rectifie, provided you have a CB400, 500, 550, or 750.  Would have been helpful to know which bike you are trying fix.

The battery itself is low impedance.  Which means if you put a very high power source on the battery, it will try to absorb what it is given.  There is no safety device, though, and high charging currents, as well as charging it when it is alreadyfull, can damage the battery.

The myth that boosting or jumpering a bike causes rectifiers to fail, likely came from an embarrased bungler that cross connected the power sources.  Then proclaimed too much power caused the fault in order to mitigate their ineptness in the eyes of others.

In the FAQ is a shop manual for the Cb550 (if that is what you have).  It outlines procedures for checking your charging system.  There is also a decent write up of troubleshooting your charging system in the FAQ, too.

A good, fully charged 12v battery, should read 13.2V.  The voltage will sag when a load is attached to it and the higher the load the deeper the sag.  The electric starter should put a very high load on it and the voltage may sag down to 10-9 volts, depending on the state of charge.  After starting and allowing time for the battery to fully recharge at increased engine RPM, the battery voltage should reach a peak of 14.5 volts, or nearly so.  This voltage would indicate that the charging system and your voltage regulator are functioning properly.  At idle the voltage at the battery will dip down toward 12V, as the alternator doesn't provide enough power at that RPM to run the bike's electrics and charge the battery, so the battery begins to deplete.  This will lower the voltage.

The statement "Usually around 12 volts",  is so inspecific, that details of whatever problem you are trying to solve are totally hidden to even experienced diagnosticians.

If your charging system is functioning properly, you may have a starter solenoid, starter switch, or starter motor issue.  If we knew how much the voltage dipped during electric start, we might get a clue about your bike's ills.

Good luck!

[marvsho17]

"Would have been helpful to know which bike you are trying fix."
- see the thread title. 

[TwoTired]

Apparently, that's where I got the impression it was a Cb550 to fix.

Perhaps, I need more sleep...

[Zane]

Yeah, maybe lack of sleep is where I got the idea there were only three diodes in our rectifier......

I used these.    http://www.honda4fun.com/home.php     (Click on "MATERIALE")

Besides the manual(s) I've taken a lot of assistance from both the parts lists and the Honda Common Service Manual.

And now (two weeks ago, in fact) much original Honda stuff is being published once more.  If you're interested in buying that stuff, check here:

http://www.motorcyclebooks.net/atvs/1976/27/4/36/811

and here:

http://www.motorcyclebooks.net/atvs/1975/27/4/8060


This guy also spreads worthwhile info for free.  I got amazingly high res parts list pix here, and used them to make my own (really sharp) 13" x 19", cross-referenced, comprehensive between 350's, 400's, 500's, 550's, 650's and 750's (including all the assorted F's, K's and SS's) CB400F Parts List.  (I made it big because I'm old, and the big drawings are so much easier for me to use......)

http://www.dansmc.com/shopmanual2.htm


Finally, Two Tired's correct; your rectifier (whcih is identical to mine) has six diodes, not three like I said.  The test I emailed you is straight from the Honda Manual and if you perform it you will be checking the rectifier properly, regardless of how many diodes the sealed unit contains.   (I guess I confused the 3 pins with the number of diodes in the thing.)  Sorry about that.  No harm done, I'm assuming??

darn it ....... I really do need more sleep!!