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

[scottly]

Thinking about taking it in to a professional...

You already have, in a way.

[calj737]

Thinking about taking it in to a professional...

You already have, in a way.

There’s some truth in that hubris 

[bryanj]

A profesional would probably not touch a modified/hacked about wiring problem without returning it to standard.
If one would contemplate it look at 6-7 hours minimum at high labour rate PLUS whatever parts HE/SHE decides are necessary!

[BomberMann650]

Difference in battery voltage and field wire voltage is too high meaning a high resistance joint somewhere.

OP's rectifier is toast and the PO's rewiring is suspect anyway.

Bomber, we have yet to determine if the rectifier is toast; first we need to verify the stator wiring. If it checks out OK, the next test is the rectifier.

Daggummit I best be gettin back to da school house then.

Thought magner had already diode tested the thing...

[magner]

With a charged battery, turn on the key and note the voltage.

With the key turned lights on and reading from the posts on the battery i get 11.9V, and reading from the bullets on the 2 field coil wires I get 10.6V

Disconnect the two field coil bullets, and setting your meter to the lowest ohm scale, measure the resistance across the white and green wires: this is on the ends of the wires that go to the stator cover, not the harness.

I’m getting right around 4.1

Next test: first, with your meter set on the lowest ohms scale, touch the leads together and note the reading. Next, unplug the connector with 3 white wires, and measure the resistance between all three wires on the stator side of the connector: A-B, B-C, C-A.

I am out of town visiting family for about a week; but I tried to do this test already. I had a hard time getting a consistent reading from the multimeter as i had to jam the test lead into the plastic plug that held each of the 3 stator wires. If I recall correctly they were each between 2 and 4 ohms.

[beemerbum]

I suspect your charging system isn't working at all.

I would bet a little bit of money on this.

Considering he just swapped the PO's battery soon after acquisition.  Then drained the new one.  I'd hedge 3:1 odds.

SOHC Hondas are for fun, not practical motorcycling. Get a BMW (Bavarian Manure Wagon) and love the old Honda. Merry Christmas

[seanbarney41]

I suspect your charging system isn't working at all.

I would bet a little bit of money on this.

Considering he just swapped the PO's battery soon after acquisition.  Then drained the new one.  I'd hedge 3:1 odds.

SOHC Hondas are for fun, not practical motorcycling. Get a BMW (Bavarian Manure Wagon) and love the old Honda. Merry Christmas

Wut?...Sure sohc4s are fun, but they are totally practical as well.  I have ridden 100s of thousands of miles on sohc4s and never been stranded anywhere ever.

[dave500]

yeah ive put thousands and thousands of kays on these fours,without spending thousands and thousands of hard earned dollars!shove ya beemer up ya bum hole!

[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,

[seanbarney41]

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

[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