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

[scottly]

Reddits "justrolledintotheshop" has taught me a little something about carbon build up.
It's not the gas that does it.  Volkswagens are notorious carbon collectors.  Seemingly on account of their crankcase oil rebreather system.
I know its for the environment, but damn.  There's got to be a better way to collect crankcase vapors!

I was to comment with something cynical on the EPA now run by Andrew Wheeler and the 'carbon' (= coal) industry he has always worked/lobbied for making millions, but... sorry, I can't. SAD! Anyway, if I ever acquire a CB550 with this blowby gas recirculating thing on it, the first thing I'd do, would be to disconnect that breather tube from the airfiltercase. There's nothing positive to say about it. Interestingly enough, when you study the fiches at CMSNL you'll see that even the later CB650 European models at least had this different than the US models.
Leaning the CB's (like the CB550K3) was a mistake and they ended up with horrible carbs. These simple engines have to be at 6% CO or they won't run right.

Getting a bit off-topic, boys.

[TwoTired]

Reddits "justrolledintotheshop" has taught me a little something about carbon build up.
It's not the gas that does it.  Volkswagens are notorious carbon collectors.  Seemingly on account of their crankcase oil rebreather system.
I know its for the environment, but damn.  There's got to be a better way to collect crankcase vapors!

Way to compare apples to oranges!
VWs have a flow through breather system.  SOHC4s don't.  No where near the volume of particle comparison.  And not a carbon problem for the SOH4.  Despite those that clutch at straws and rely on innuendo instead of science for vilification.

Honda ifentified the need for de-coking even on models that didn't have the crankcase recirculator.  ...Which provides the very nice benefit of evacuating water vapor from the crankcase.  Who likes brown mayo?

[magner]

Alright y’all finally got my multimeter and tested the bike out! Charged the battery and it read 12.45 with the bike off; 11.9 when I turn on electronics, and it doesn’t budge from 11.89 when i start the bike, or rev it up to 4000. So it looks like y’all are right and  my charging system isn’t doing it’s job at all!

[magner]

Welcome to the SOHC/4 family.

Thank you so much! When I get home tonight I will try and get as many pictures as I can take that will be of help! I also have a video of the multimeter reading while starting and revving the bike if it is of any help.

[scottly]

Don't bother with the video. If this were a stock wiring harness, we could tell you exactly where to check voltages etc, but since your bike is not stock, we have no idea where to look. For all we know, the PO never installed the components required for the charging system to work. See if you can find a device with 3 yellow wires: this will be the rectifier.

[Ichiban 4]

Hi guys! LOL
Don't usually weigh-in on these extended technical/philosophical conversations..but simply wanted to add that after about 20 years of riding my '77 550K..found that the best way to maintain/preserve battery life..was to get a higher cranking-amps battery (from stock 12 Amp hour to 20 Amp hour AGM..and put on Battery Tender maintainer when not being ridden). I can ride all day in stop-and-go traffic..no problemo.

I agree whole-heartedly w/opinons expressed on this thread..that these bikes were not engineered haphazardly by Honda.  Perhaps @ the end of the 550 SOHC4 era..they (Honda) were not thinking much in terms of maximum electrical efficiency.  But the higher capacity batteries solve a lot of that problem..from my experience. And as has been said many times on these forums before..putting these old bikes on battery maintainers during the interim..usually solves most of the battery problems..especially with the 500's and 550's

My two cents here..

Al/Ichi

[magner]

See if you can find a device with 3 yellow wires: this will be the rectifier.

https://imgur.com/a/ARAvsad

Apologies for the delay! Here are a ton of photos that I hope are helpful, as I'm not entirely sure what I'm looking for. I definitely CAN NOT find anything that looks like the reg/rec units I've seen...

Thanks y'all
Andy

[scottly]

In the last pic, there appears to be a shallow aluminum box, filled with black epoxy: this is probably the reg/rect. There is a plug next to it with three white wires, which may be the wires from the rect to the yellow stator wires? Any markings on the other side of the box? What are the colors of all the wires going to the box?

[magner]

A picture from the left side of the bike, focusing on what’s beneath the seat will help.

The stator lives under the left side of the engine cover, the round metal cover below the pistons.

https://imgur.com/a/O2039x5

Updated album! I apologize for my terrible pictures, my garage has one tiny light and no electricity otherwise... what should I start testing/what am I looking for next?

[BomberMann650]

It appears whoever rewired that bike tried to give a second sh!t about it.

Thing with three white wires looks generic as can be.

[scottly]

The part with three white wires appears to be only a rectifier, not a combination regulator/rectifier. You will have to unbolt it to see if there are any marks on the other side.
The black thing is a blade-type fuse holder; the cap slips off and the fuse is under the cap. Is the red wire from the rect connected to it?
The round thing with the two posts is the starter solenoid; the post with several wires is connected to the battery plus terminal.
There a two groups of wires that enter under the shifter cover; one has three yellow wires, which should be connected to the three white rect wires. These are the Stator wires.
The other group has a green wire and a white wire. These are the Field coil wires. The green wire should be connected to ground, and the white wire would normally be connected to the regulator. What is the white wire connected to?

[HondaMan]

A VERY IMPORTANT question: under your "HONDA" timing cover, what type of ignition is in there? Is it points? Is it Dyna S? Is it the [cheap] Chinese 2-sensor trigger unit from eBay?

If you have anything but points under that cover, there will not be enough electrical power generated to support the bike with the tiny battery.

[BomberMann650]

A VERY IMPORTANT question: under your "HONDA" timing cover, what type of ignition is in there? Is it points? Is it Dyna S? Is it the [cheap] Chinese 2-sensor trigger unit from eBay?

If you have anything but points under that cover, there will not be enough electrical power generated to support the bike with the tiny battery.

Sorry, but that is simply not accurate. Whether he has points or electronic ignition is rather irrelevant to the size of the battery. What is relevant is the running rev range he rides at. If he operates the bike mostly above the 2,500rpm threshold of the 550, then his bike will be always be in a surplus charge state, and not drawing down the battery. Even if he operates below that during some periods of traffic, regeneration of the storage is possible.

Having said all that, I would not choose a battery that small either, but I would not point a finger at his ignition as to the primary concern over battery size and call it emprical evidence.

If magner added an OMP Vrrem4-sohc to the system, it wouldn't matter much what else is in the bike.  That part would deliver reliable voltage.

[magner]

Is the red wire from the rect connected to it?
What is the white wire connected to?

The red wire from the rect goes straight into the post of the starter solenoid with the other connections; the fuse on the blue wire that also comes out of that solenoid post is for a quick connection to a battery tender. The aluminum unit has no markings on the bottom or anywhere! I can see the green and white field coil wires but I will take off the shift cover tomorrow to see what the white connects to.

The ignition is points but it looks like it might be a newer replacemt unit.

Should I go ahead and order a new reg rec unit? Will it be a pretty easy swap?

[scottly]

First find where the white field is connected.
Your points and plate are stock TEC stuff; put the cover back on.

[Deltarider]

Your points and plate are stock TEC stuff; put the cover back on.

I'm with Scottly and I invite everyone here to have a close look at your (Magners) OEM points plate. You do not often see them so tidy. Bravo! All the little rings are still there, the crossheads are not battered, the little felt looks like new and look how both breakerpoints and plates are more or less in the middle of their adjustment range. This is how Honda designed it. Honda also intended to use genuine Honda parts only.

[PeWe]

The felt (drained with grease) must have contact with the rotor. Old rotors can have scores or old residues that will file the points bakelite causing less gap quicker than needed.
The rotor can be refreshed by sanding it if surface look or feels rough.  I used grit 400, 800 on mine making them to look much better.

Stock charging system work fine. I do not trust the later cheap China made regulator- rectifier. Burns the voltage to correct level, short to ground?

My bike has a LED that show actual voltage when parked as well as when engine is running. This told me that I had to adjust my stock regulator since I saw some occasional overvoltage.
LED H4 (maybe 30W) headlight make it possible to ride longer periods on less than 4000 rpms without getting too low voltage as happen with std halogen H4 that take 55W.

I charge my batteries every month (min every 2:nd) 1-3 days with CTEK charger, MC mode, max 1 A. I think 0.8A. I have an extra battery (cheap GEL) on the shelf that must be maintained. My CB750 K2 project will get it.

[magner]

First find where the white field is connected.

Here is the view under the shift plate and the wires that come out and a #$%*ty diagram i made https://imgur.com/a/gghFcZm

I can see the 3 yellow from the stator, and the green and white from the stator, and a green/red wire and a red wire from unknown components. All 7 go into the housing to go up to the top of the frame, but only 5 come out the top of the housing (2 towards the front of the bike, and 3 that go into the white wires for the rec) so I guess 2 must stop somewhere in the housing. Thanks for all the help, I’m really not sure what to do here. Thinking about taking it in to a professional...

[Deltarider]

Without having overread all the above, here a warning in general for CB500/550 owners. Where the wires exit the top of the left crankcase cover (aka sprocket cover), there's a chance the harness becomes chafed. Easy to address with some vulcanic tape.

[flatlander]

Thinking about taking it in to a professional...

don't do that, most shops won't have the knowledge to deal with these old bikes properly or won't take the time for it.
the advice you get here will help you to sort this out yourself, better than a shop could do. you will learn as you go, it will take some time and effort but that's the joy of owning a vintage bike.

[scottly]

The green wire with the red stripe is the neutral light, and the blue wire with the red stripe is the oil pressure light. If they both function normally, it means the white and green field coil wires aren't connected. This would certainly explain why your charging system isn't working.  You will need to either slide the shrink tubing or cut more away to expose the area where the stock wires are spliced to the new to verify. Don't give up; you're almost there.

[magner]

Thanks for the encouragement! I’ve confirmed  that the neutral light and oil pressure light wires are cut and stop within the housing (makes sense as I don’t have those lights), and the white and green field coil wires splice each into new blue wires. Of course the new wiring harness uses this same blue wire for all wires so it’s hard to trace and I’m trying to avoid cutting open all of the harness housings unless I absolutely have to... I am certain that the field coil wires run to the front of the bike along with a bunch of other blue and black new wires. I studied the stock wiring diagram to try to deduce which wires are which. Out of these wires in that housing, 2 run into the coils (I assume these come from the points), 2 into the ignition key switch, and the rest run into the headlight bucket where they connect to the headlight switch, front brake switch, headlight bulb, tach, and the into the right handlebar control. Should I hack open the harness to see exactly which thing it runs to?

PS: Is it appropriate to message the PO about this, seeing as how he sold em a ready to ride bike which I have yet to be able to ride...

[BomberMann650]

Probably won't get much sympathy from the previous owner.

Some people

[scottly]

Try this: there are bullet connections for the white and green field coil wires under the shifter cover. Try to slip the positive meter probe under the clear sleeve on the white wire so it makes contact with the bullet, and connect the negative meter probe to the green wire the same way. With a charged battery, turn on the key and note the voltage.

Since it looks like the shrink tubing wasn't shrunk, you may be able to identify which blue wire goes where by pushing and pulling on the wire in question, and checking for movement on the other end.

I would contact the PO and ask how he wired the charging system; ask him if he wired it for an excited field system or a permanent magnet field. 

[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

I was able to identify that the white field coil wire travels into the headlight bucket and solders into 3 wires that look to be original (2 blacks and a green with red stripe). These 3 wires go into a shrink tube along with gold/white stripe, red/yellow stripe, and black/white stripe; and all 6 of these go into the right handlebar control (which is stock). I guess this means there’s no regulator?? Could this be the issue? Not sure why that wire splices into 3 separate wires for the handlebar control...