83 CB550 Recharging Issues

[theeville]

Hi all.

I bought my first bike, a 83 Honda Nighthawk 550 off a coworker a few months ago because he couldn't get the clutch to engage and he needed money for his Mustang project. Since then I've fixed the clutch issue and now the bike runs pretty good. Only issue is, it doesn't want to charge the battery.

Long story short, before I bought the bike the stator was rebuilt, and then I bought a new battery and a new regulator/rectifier for it as well as replacing the neg cable from the battery. Still no go. Only thing I can think of is a short somewhere. I did a quick check on the wires that go from the stator/regulator/battery, and all look fine.

My question is, is there something I am missing? And is there an easier way to find out where the short is if there is one? Something I thought up was if I would pull fuses to the headlights, etc would I be able to determine where the short is assuming the battery then charges?

The bike runs fine otherwise, except the carbs do need to be cleaned. All lights work, stator seems to be working fine. I've probably put 400 miles on it already when it does start up.  Thanks!

[happycommuter]

 
Um, how's the alternator rotor?
That's all I can think of.

Also, did you do the lazy test of blipping the throttle and seeing if the headlight gets brighter?

[gammer]

The thing that jumped out at me was the "rebuilt stator"...which I assume you mean 'alternator'. Just because its rebuilt doesn't mean its working 100%
I would check the specs on it and test it.

[theeville]

Yeah, it is the stator that was rebuilt.  I've driven it 150miles one trip already, and never had power issues.  It's just that after 6 or so restarts, the battery is drained enough to not start the bike.  The lights dim and get brighter whenever I give it throttle or change gears, which seems to be normal.  I agree that I wouldn't trust a rebuilt stator 100%, but AFAIK, the stator is fine.  But I'll try and test it tomorrow.

[happycommuter]

Wait, what are the symptoms here?  If the headlights glow hotter, and you're getting 150 miles without dying, why do you think it's a charging issue?

If you're talking about six consecutive (failed) starting attempts, that's asking a lot of the battery, and is a sign that something else needs attention too.

The battery was discharged at least once, it seems.  Charge it, test voltage across terminals or be more thorough and bring it somewhere for a load test.

[theeville]

What I mean by 6 or so successful restarts is that the battery has enough charge for the bike to start until then, meaning the battery isn't being charged.  I can run the bike all day long as long as I don't shut it down.

And I did test the battery just this past week.  I charged it up, left it sit for a day and read 12.8 volts.

[MrF]

What's the voltage across the terminals when you're cranking with the charged battery?  I'd also be curious how many volts you're getting once it's started with the engine at a decent RPM (~3000).

Oh, and Welcome!

[theeville]

Thanks.

I had my roomate take a look at it while I ran it just now.  Go figure, the bike started right up without jumping it.  At 3k, it read 12.4v.  Idle read 11.9-12v.  I left it sit idling and revving it a bit for about 5 minutes, shut it off and tried to restart, and no go.  Battery read 11.4v. 

I almost positive the battery is good.  Acid level is fine.  What we have come up with is a short somewhere.  Before I bought it, it did sit outside for a couple years in the rain/snow uncovered.  Any common place I can start looking for a short?

[happycommuter]

Can't say I know of any known voltage drain spots.  The old test is to disconnect the battery and put an ammeter across the cables.  In cars you allow a few amps for clocks and stuff, but there should be almost no current being drawn.  If there is, you keep unplugging things till it goes away - last thing you unplugged is the problem.

[gammer]

Yeah, that does sound a bit low. At 3,000 RPM your voltage should be around 13.5v

[theeville]

Yeah, that does sound a bit low. At 3,000 RPM your voltage should be around 13.5v

I won't get a chance to look at it again for another couple of days.  Would a short cause it to not charge up to around 13.5v?  I'm in denial in believing the stator is screwed up.  I just replaced the back tire a month or so ago, and told the bike shop (reputable shop, had 5 different guys from the MSF course refer me to them) to check the stator, and said it was fine.

Thanks guys.  I'm planning on completely restoring/painting the bike this fall and was hoping to get some miles on it before then.  First bike, first project.  I can't wait 

[happycommuter]

I see no reason to believe the battery is still any good.  It's been discharged a good amount at least once, and you don't seem to mention putting it on a charger.  A good battery will read 12.6 or higher across terminals and stay that way for a while (leave it disconnected if you're worried about a short in the bike).  Check the easy things first and assume nothing.

[Flashhawk]

I think I would have the battery load tested, you could have a combination of a going bad battery and possible starter slightly dragging which could be draining the battery during starts, especially hot and repeat starts.

Also I have seen a few fuse panel problems with loose and corroded connectors, may be another place to look, also inside the fuse panel.

Good Luck!

[layback209]

Welcome to the forum.

Sounds like the exact same symptoms my bike was having.  Seems like all the hawks before 84 are catching the same bugg lol.

http://nighthawk-forums.com/index.php/topic,215.0.html

See the above link for your refference.

What fixed mine  was:
     1. Running it everyday
     2. New Battery (i thought the old one was fine
        because it could start the bike every once
       and a while, misconception for me the
       battery was toast had the voltage but not
      the output current for starting.  All about
       current)
     3. Locating a short Circuit in the fuse box
        behind the horns.  Was the bottom 2 clutch
        side push in connections.  THe possitive
        leads melted and made a mess.  A bit of
        cleaning and a bypass splice later problem
        was fixed. Going through all the Hot "power"
        conections to the fuse box checking for
        corrotion.
     4.  If my bike would not start in its own i could
          push start it (gotta get home lol).  Some
          times if a 4-stroke like this floads it very
          difficuilt to start.  I found pulling the plugs
         drying them with a lighter works.  Or if you
         don't want to do that push starting will
         work, just make sure you get some one to
         help push.  You may have to push it for 2-
         blocks before it catches ;). 

Hope that gives you a couple ideas.  Keep us updated.

Cheers,

[theeville]

Thanks for the replys!

I pulled the battery yesterday and put it on a charger for the night.  Checked it this morning, and it was holding at 12.8v.  I'll check it again tomorrow, but it seems to me the battery is still good.

I did run the bike yesterday before pulling the battery.  The bike cold starts right up (with it jumpered to another battery) with just a little bit of choke.  But with it warmed, it still only outputs 12.5v to the battery.  This was with all the fuses up front pulled.  I do have a clymer manual with it, and the output test says wait until it stabilizes at 13-14v, but I have yet to see it go over 12.5 at any RPMs. 

Now, on another forum someone mentioned bridging the starter relay to bypass the rectifier.  Would this make a difference with my situation and how exactly does this work?

I'll try to get a chance to take a look behind the fuse box sometime in the next couple of days to see whats going on back there.

And as far as push starting it... Yeah I've already had to do that twice now.  First time I've done that with a bike... I was expecting it to take off on me