Topic: '76 Honda CB550F: Suggestions for Better Battery Life?

[TwoTired]

25 years of reliable commuting on Sohc4s say it is practical as well as fun.
But, a machine is only as good as its mechanic and reliable as well as its maintenance.

Didn't I read a mag article that said the machine was less remarkable than others (mostly brit bikes) because of its steadfast reliability. Few bikes back then could be driven off the showroom floor and on to coast to coast to coast to coast travel, with only routine tune up maintenance.  It was when unenlightened owners modified them when they didn't simply work at the push of a button.

But, those were the days where it wasn't mainstream fashion to make them racing only bikes, (by rank amatures) and then purpose them for street show bikes.  The ones that were modified so, didn't survive to be used today.  These became "parts bikes".

Cheers,

thats a bunch of crap too    This is the bike that has gone the fastest, farthest, most dependablest (I know)
20180908_195337 by Sean Barney, on Flickr

Of course there are rare exceptions.  But, I'd expect a tally of stock non-cafe'd survivors to far exceed the tally of race modded survivors.

I tried to take a poll on this forum about how many 70's and 80's cafe'd bikes had survived to modern times.  I think there were two who responded.  Plenty of newcomer, newly made cafes, though.  Fad bikes don't normally last more than 5 years before dereliction, in my experience.  I Actually have one, modded in the 80s riden a year or two, then abandoned 20 years before it was given to me.  Yep, parts bike.

Cheers,

[seanbarney41]

I agree with that, somewhat...but will refrain from cluttering up this thread anymore with anecdotes that don't relate to getting the op's bike charging again.

[bryanj]

When i was in the trade customers would get upset when they wanted to trade in their customised pride and yoj and we subtracted from the value the cost of putting it back to standard explaining to them we would need a customer who thought exactly like they did to sell as is.

[magner]

I am back home and tested resistance on the 3 stator wires again; all 3 read right at 00.9 ohms.

Also I went ahead and ordered a shiny new reg/rec from common motor as well as an H4 headlight and lens. When it comes I will most likely have some questions about hooking it up since some wires will most likely need re-routing.

[scottly]

The 3 loose wires are the regulator portion. The black wire needs to be fed +12V when the key is on. The wire that is now connected to the white field coil wire appears to be switched +12V. Disconnect it  from the white wire and connect it to the reg black wire. Connect the white field wire to the reg white wire.
Connect the green reg wire to ground.
The green field wire is already connected to ground, so it's OK as is.
On the rectifier side, the red wire gets connected to the Battery + terminal at the solenoid, the green wire is connected to ground, and the 3 yellows are connected to the 3 yellow stator wires.
Also, do another test on the field coil: with both bullets disconnected, check for continuity from the white wire to ground. There should be none; the meter should show the same reading as when the probes aren't touching anything.

[magner]

Thanks that helps a lot!
This the only part I'm a bit fuzzy on:

The wire that is now connected to the white field coil wire appears to be switched +12V. Disconnect it  from the white wire and connect it to the reg black wire. Connect the white field wire to the reg white wire.

When you say disconnect it, do you mean at the bullet connector down where the white field coil comes out of the stator cover? Am I connecting the white and black from the new unit to either side of this disconnected bullet connection?

[scottly]

I would disconnect it at the point where the blue(?) wire is connected to the white wire, not at the bullets down below.

[magner]

Okay! So to be sure: blue side of that wire connects to black reg wire which will supply it with switched +12V as input for the reg, and the white wire coming out of the reg will connect to the white field coil side of the wire therefore outputting the regulated power into the stator. Am I understanding this correctly?

[scottly]

Close. The regulator adjusts the power through the field coil, which is an electromagnet. This magnetizes the rotor, which, with it's alternating north and south poles, generate a 3 phase alternating current in the stator coils. The rectifier changes the AC to DC, which charges the battery. 

[magner]

Also, do another test on the field coil: with both bullets disconnected, check for continuity from the white wire to ground. There should be none; the meter should show the same reading as when the probes aren't touching anything.

Got everything hooked up (best as I can). I did the field coil continuity test with the bullet to ground and I am getting a reading of about 10 ohms 

[scottly]

This is with both the white and green wires disconnected at the bullets? If so, the field coil is bad, and needs to be replaced. Dave500 recently posted about how too long of mounting screws could damage the field coil windings.

[magner]

This is with both the white and green wires disconnected at the bullets? If so, the field coil is bad, and needs to be replaced.

It’s finicky but it’s reading something... is this the solution as to why I’m not getting any voltage increase at all: because the field coil isn’t producing any charge at all? I hope my reg/rec upgrade was not worthless 

The only field coils I see for sale are on eBay and very rusty... is this recommended?

[TwoTired]

The field coil on a 550 should measure 4.8 ohms if the measuring device and set up is accurate.
But, you need confidence in the measurement to be confident in a part diagnosis.  It is easy to have things make the measurement higher the real.  A faulty meter is one. Test lead resistance is another, bullet connector corrosion resistance can add to the field coil measurement reading.
Can you locate a 5 or 10 ohm resistor to verify your test equipment accuracy?

A ten ohm field coil in this bike, means the magnetic field strength for the alternator will be weak.  Ergo the stator output will also be weak.  Possibly weak enough that it can't even overcome the electrical load of the bike to charge a battery.  It should produce something.  But, you may have to disconnect electrical loads, like lighting, to find out how much it will give.

If you can't verify your meter calibration, the next best thing is to verify that the connections to the field coil are clean and well connected with low resistance.  It is also posible that connecting full power to the field coil constantly, as in prevoius wiring, has over heated the coil, melting coil wire insulation.  But, this usually results in the wires shorting together, which lowers the resistance reading measurement.  This is why test technique to obtain an accurate reading is imortant to avoid replacing parts the are actually good because of a false test procedure.

Cheers,

[magner]

I am a bit confused... are you referring to the same test as scottly, wherein I am unplugging the 2 field coil wires and testing the resistance between the white and green wires connected to the field coil (like in the picture)? I thought I was looking for it to read 0L for open line.

I am having a hard time getting a good clean reading as it changes constantly depending on where the probes touch the bullet tip of the wire. Maybe they need cleaning? Also I’m not sure if this matters but with the key on there is plenty of magnetism to hold a paper clip to the casing of the stator.

Thanks!
Andy

[bryanj]

The wires must be disconnected to test and then there should be zero magnetism with key on

[MauiK3]

Can't we all just get along?
I'll add that I keep any equipment and vehicles that are used less than daily on a battery tender. Keeps the batteries fresh. If the 500 was on one each night it would help make up for the commute.

[TwoTired]

I am a bit confused... are you referring to the same test as scottly, wherein I am unplugging the 2 field coil wires and testing the resistance between the white and green wires connected to the field coil (like in the picture)? I thought I was looking for it to read 0L for open line.

I am having a hard time getting a good clean reading as it changes constantly depending on where the probes touch the bullet tip of the wire. Maybe they need cleaning? Also I’m not sure if this matters but with the key on there is plenty of magnetism to hold a paper clip to the casing of the stator.

Thanks!
Andy

I'm thinking you may be more than a bit confused.  I don't want to speak for Scottly.  Maybe you'd prefer to wait for his response.

Of course you clean the bullets....AND the sockets!  Corrosion is resistive and increases the measured resistance!  The only alternative is to pierce the corrosion coating with a very pointy probe.  That will gain you a better measurement possibility.  But, unless you clean the corrosion coating, it won't help alternator function in circuit.

IIRC, On the 550, there is only one wire available that reaches from the field coil to the regulator, the White wire.  The green wire at the regulator attaches to the frame/motor and the field coil has its functionally "green" wire attached to the motor case.

The field coil is exactly that.  A coil of wire with two ends.  One is connected through bullet style connectors under the drive sprocket cover.  Yes, that one can become resistive, also.  So check it.

The "logically green" wire of the field coil connects to the green at the regulator via the motor case -> to frame -> to the harness green wire connection.  If the motor isn't electrically connected to the frame (think paint insulation), the regulator can't properly drive the alternator field coil.

If you expect the alternator/regulator to do their job, the regulator must "see" a field coil load of ~4.8 ohms at its terminals, not 10 ohms. 

So, either correct the connectivity between field coil and regulator, or measure the field coil as near to the field coil proper and determine it is actually 10 ohms (proven failure) or 4.8 ohms (which would prove your issue is elsewhere than the coil itself).

And finally, if your test equipment is lying to you, you aren't ever going to make any sense of this issue.  So, take steps as outlined previously, to gain confidence that your measurements aren't further confusing the resolution of your charging troubles.

Carry on...

[scottly]

Lloyd, perhaps you missed that the 10 Ohm reading was between one of the field coil wires and ground?
Andy, you did need the new reg/rect, regardless of what else is wrong.
Let's revisit testing the field coil. First, there is always confusion between the stator and the field. Here is a pic a of a 400 stator and field; your 550 is similar. The stator is on the left, and the field is on the right. This is to give you an idea of what's on the other end of the bullets.

[scottly]

A set of test leads will alligator clips (AKA roach clips) greatly simplifies using a meter, and the teeth of the clips can get a good connection on the bullets.
First, connect both meter leads together, so you know how much error your meter has. This meter shows .2 ohms when it should read zero. Other meters I have read as much as 1.4 ohms.

[scottly]

Next, connect the two meter leads to the two field coil wires. This 750 coil reads 7.2 ohms, so 7.2 minus .2 = 7 ohms, which is in spec for a 750. Yours should be 4.8 +/- 10 %.

[scottly]

The continuity test from one of the coil leads to ground is shown is this pic. One of the meter leads is clipped to the body of the coil, which is grounded to the motor when installed. The windings of the coil are insulated from the body, and any reading indicates the insulation is compromised. If you have an auto-ranging meter, and your fingers are touching the probes, you will get false readings. The test leads allow hands-free measurements.
 

[magner]

https://imgur.com/a/HqAyLpI Thanks for the helpful pics; here are my corresponding pics! Looks like 1.2 ohms resistance on just the alligator clips, and 5.3 on the 2 field coil wires, so 4.1 on the field coil. I get no continuity between hound and either field coil wire.

[scottly]

The 4.1 ohms is still below the spec in my manual of 4.9 +/- 10%, which at the low side would be 4.41. I think I mentioned before that running the field coil current WFO all the time *may* have over-heated it?
Post an ad in the Wanted section of the classifieds.

http://forums.sohc4.net/index.php/board,182.0.html

[RAFster122s]

If running it WFO overheated it, then it may have exceeded the thermal limits of the wire's coating. Magnet wire uses various types of coating and I once had learned about it but I've forgotten those details. The Temp of the wire can sometimes be 150C and other wire is made to withstand 165C or higher. Yeah, pretty hot!  But, in the center of a winding if it builds to that temp it will breach the winding and then you end up with a short which could account for the lower reading.
All of this is merely speculation. Bottom line is it is out of spec as Scottly pointed out and better safe than sorry, replacing the coil is a wise move or a move towards results which should work when everything is within spec.

David

[magner]

https://imgur.com/a/pnB4oVv

Sorry for the radio silence, but I was too busy out riding my bike! I installed the new reg/rec with the help of you all and a family friend, and my battery is now charging with ease! I have been able to ride to and from work many times now, sitting in terrible traffic, and my bike has been perfectly fine. I have run into a few other small issues that might get their own thread later on, but for now I am just enjoying the bike! Thank you all so much, I honestly thought I wasn't going to be able to do it, but am proud to say I did!

Cheers,
Andy