Topic: 1978 Honda CB550 K4

[GodinJ]

Hello everyone! New to these forums, but was told this was a great place to look when troubleshooting my bike and it certainly looks that way. I'm the owner of a 1978 Honda CB550 K4. Bought it from a guy near where I used to live with only about 2500 miles on it. It's up to about 3500 now and I was finally able to get it over to where I'm living now. I absolutely love riding it, but have noticed a couple things.

First and foremost, the battery is not staying charged.

-I never seemed to have trouble with the battery while riding before, but it's been dying as of late. I bought a new one thinking it was the battery that was bad, but the new one is already dead after about a week and a half of riding. I bought a battery tender junior to hook up to it overnight for the meantime, but was wondering if it's maybe the stator or regulator? Anyone else ever have a problem similar to this? I'm quite a novice when it comes to motorcycle repair, and am even more green on anything to do with the electrical system.

Second, it seems the clutch might be a bit wonky.

-I noticed this after riding it for a while on some highways. Once I started shifting down after running into a stop sign, the shifter was being VERY reluctant going into first. Like, it'd resist me pressing down on it. It's only happened two or three times, so I'm not sure how big of a deal it is.

-I also noticed that sometimes, when shifting up a gear, it'll only go "half way" and I'll be in some sort of pseudo-neutral state. It's a quick fix as I simply have to shift up again real quick.

-I talked to the previous owner of the bike, who took really great care of it, and he suggested that it may just be that the clutch needs some tweaking, as it has been a while since the bike was ridden. Sounds like a reasonable explanation to me, but I'd like a second opinion to be sure.

 Anywho, that's about it for my questions. I love riding the thing, and really want to make sure I can continue doing so for as long as possible!

[Bankerdanny]

Welcome, your bike looks great.

You need to hook up a multimeter to the battery while the bike is running and check the voltage at the battery. Bring the engine rpms up to about 2k, the voltage at the battery should be in 14 volt range. It is possible that you need a new regulator (although with only 3500 miles you shouldn't), but I would check all the connections coming from the generator to the regulator (which is what controls the amount of power that the battery receives from the generator) and then the regulator to the battery as well as where the ground cable from the battery is attached to the frame. The problem is most likely a corroded connection that is keeping the power from making it to the battery.

The clutch is adjusted by a nut on the right side down by the front peg. There is a nut that controls the amount of slack in the clutch cable. You need to adjust the tension on the cable, if there is not enough then it will not fully disengage and make it hard to get into first. Once you are moving full disengagement is not as big of an issue, which is why you don't have problems in other gears.

Download the repair manual available at the link in the 1st topic at the top of the page, it will tell you how to adjust the clutch, it is a very simple job and should solve the 1st gear issue.

[GodinJ]

Great! Thanks for the swift reply!

I'll be sure to get a hold of a multimeter and see what I get hooking it up to the battery. I'll also be sure to check the path from the generator > regulator > battery > ground. Though I'm not 100% sure where to look for the generator/regulator. I should be able to figure it out though! I hope it's simply a corroded connection so that it's an easy fix, but I suppose anything more complicated would help me learn more about the bike anyhow.

I do have a service manual, but it's back where I used to live so I don't actually have access to it currently. I'll be sure to download the repair manual though, it sounds like it'll be very helpful.

[Spanner 1]

Bankerdanny +1..... Have a close look at the 6 or 8 way white plug that feeds down thru' the engine case to the stator/field coil.  You will see it with the l/h sidecover removed. Has 3x yellow, white, green and 2 more.....
Also as a side note, those high pressure do-it-yourself car wash places are not for bikes, ever 
The water get's into all the connectors and DESTROYS the electrical with corrosion, just sayin', rant over 
Oh!, and welcome to the Forum, that looks like a beautiful 550...

[Bankerdanny]

I like having both the hard and electronic versions of my manuals. I bring my laptop with me to the garage when I work on my bike.

The generator is located in the round section of the engine case on the left side. The points and condensor are in the same spot on the right side.

The regulator is located on the left side behind the side cover with the fuse box and various relays. It's a black metal thing with cooling fins.

Start with the electrical connections. Given the age and very low mileage on your bike that is the likely culprit. Start with the ground strap connection at the frame. Remove it and give the cable, the frame where it connects, and the nut a good scrub with a wire brush.

Fast replies are a feature of this board. My '77 died at a light not long after I got it back on the road last year. I kind of guessed the issue from things I had read here (be a regular visitor, you pick up all kinds of great knowledge), a bad connector at the ignition swtich. I left it in a parking lot at Midnight and a passerby, who turned out to be a CB400F owner and member here, gave me a lift home (about 5 miles). I posted something before going to sleep, and when I woke up the next morning the solution was waiting for me. I was able to basically hot wire the bike to get it to run and ride it home where I was able to solder the connection to fix it.

[TwoTired]

The age of connections can be an issue, as the materials used can oxidize and become resistive (losing power) over time.
Cleaning all the connections, switches and fuse clips is one way to deal with this.  However, to find out if this MUST be done only takes a voltmeter to measure the difference in potential between the battery posts and the connections to the regulator.

With the bike switched ON (doesn't need to be running if the battery is strong enough), place one probe on the Battery POS terminal and the other on the Black terminal of the Vreg.  Note the reading.
Then place one probe on the Battery NEG terminal and the other on the Vreg Green terminal.  Note the reading.

The sum of these readings is the error being reported to and what the Vreg operates using.  If more than .5 Volts total, it means a chase down of the offending pathway component(s) is in order.

About the shift issues.  A dragging clutch can definitely cause them.  Some tips to help is to do all gear changes while the rear wheel has some rotation, this helps new and crisp gear dogs to find their slots, rather than the spokes that can block movement in the gear wheels.

Do make your shifts a positive stroke and don't "short stroke" the lever with "lazy foot".

Oil type and condition can play a factor as well.  The clutch plates have very little clearance between them when not engaged.  This allows "Viscous Coupling" which places rotational pressure on half the gear mesh components.  Old, "worn out" oil will increase the coupling as much as using the wrong oil.  I won't say any more here so as not to spark another rabid "oil debate".  I'll just say that owner manual recommendations should be heeded, and note that "energy conserving" oils were not available when the bike was first built (mostly likely why it is not addressed in the owner's manual).

Nice bike you have there.  I have one too, but the clear coat is peeling off the tank from California sun damage.

Cheers,

[Sniper X]

Nice clean CB550! If not yet mentioned, get hold of a VOM (volt ohm meter) and do the following. Start the bike with the sea open and the battery terminals accessible. Whilst at tick over (idle) touch the red probe from the VOM (set to VDC) on the red or hot terminal of the battery, touch the black on the ground of the battery, watch the reading and as you watch it, rev the bike at least fo 3000 rpm. It should get up to ABOUT 14v. If not chances are the stator (alternator) or rectifier or voltage regulator is bad. If not the wiring...check to see if the wiring to the bike from the alternator is in good nick (conditino) and if the terminals on it are clean.

[lucky]

Can you tell us what kind of camera you used to take the photos shown?
They are excellent to my eyes.  Thanks

[Stev-o]

Welcome and beautiful bike. Get a good multimeter and follow thevgood suggestions above.
Most likely, it is nothing major. Good luck.

[LesterPiglet]

That's a lovely looking bike. I wish my seat looked like that.

[GodinJ]

Thank you everyone, for both the help and the compliments!

I looked at the bike today and learned two things.

1) I have no idea how to use my friend's multimeter.

and

2) My bike's left hand panel has a lot of dust under it!

I think the problem with the multimeter was less user error and more hardware error though, to be honest. My friend said it was a bit cheap and he got it secondhand from another friend, so I think the thing was a bit wonky to begin with. I will be giving it another go tomorrow at another friends house who I know has a working mutlimeter (and I'm fairly sure he knows how to use his haha).

However, I was able to take Bankerdanny's advice and clean off the ground connection. The only bit that seemed to have any corrosion on it was where it actually connected to the battery though, as following to where it connected to the bike looked like this:



so it was fairly clean!

Question though: in the above photo, what is the black thing to the left? It has that thin metal attachment that connects to something else and I wasn't sure how delicate it was while removing the nut that was connecting the ground to the bike.

Taking Spanner 1's advice, I removed the left hand cover to take a look at the electrical system there and was greeted with this:



I thought that seemed a bit dusty and tried using some compressed air to clean it, but that was to no avail. What would be the safest way to clean all of that? A wet rag? Not sure if the dust will come off without a fight.

Anywho, it was fun poking around the thing while it lasted. 100+ degree weather didn't make standing outside too thrilling though, so I cut it a bit short. I will be sure to go at it again tomorrow with a better multimeter. The battery is charging on a Battery Tender Jr. at the moment, so hopefully that'll be enough to keep me riding tomorrow.

In regards to your question, lucky, the camera I've been using is actually my phone camera. It's an iPhone 4S, so the camera is quite nifty (either 5 or 8 megapixles, I forget).

Once again, thanks for all of the advice and compliments, I will try my best to post an update ASAP!

P.S. What would the best way to disconnect the turn signal beeper be? I don't mind it too much, but it seems awfully loud.

[LesterPiglet]

From looking at your pictures I would say everything is absolutely perfect but you must do regular checks on a motorcycle. Wet rag and detergent, don't have it dripping. 

[bollingball]

All you have to do with the beeper is unplug it. the wires should be covered if not cover them with tape. That black thing is your rear brake switch.

Ken

[Stev-o]

The "black thing to the left" is your rear brake light switch. Push down on your brake, you will see how it works.

Go buy a multimeter,they do not cost a lot, and you will need it.

Multimeter 101: turn switch to DC voltage. Touch red lead to + (postive) post on battery and black lead on - (ground), then read meter, should be between 12-14 volts.

[ChrisG13]

I have been trying to track down an electrical problem on my bike bought a new battery and rectifer but I still dont have power to the controls turn signals, horn, and ignition. What are my options? Is the a blade fuse somewhere or something I may have missed?

[Bankerdanny]

Chris, Start a new thread and include (1) the year and model of your bike (2) details on any modifications to the electrical you are aware of and (3) tell us what diagnostic work you have already done.

All fuses are located under the left sidecover.

Why did you buy a rectifier?

[Duanob]

Sweet example of a late model 550!

+1 on going through and checking and cleaning all your connections. Most of them are in  the headlight bucket but the important ones are under the fuse panel located under the left side cover. Three bolts to pull it away from the frame to see what you got. I used this FAQ and it helped me pinpoint my charging problems but only after I bought a bunch of parts that I didn't need.

http://www.oregonmotorcycleparts.com/FAQ.html

[LesterPiglet]

Quite a few connections under the tank that accumulate a lot of sh1t. Don't forget those.