Topic: rebuilding honda cb550f, electrical problem

[martijn]

Hello there!

Short introduction; my name is Martijn (but for all you english speaking folks out there, Martin). I am based in the Netherlands. I have some experience with rebuilding mopeds (honda ss50) and so it seemed like a nice idea to restore on of its big brothers and my all-time favourite motorcycle; a honda cb550F

I saw a very knackered old chopperised cb550f and I strongly felt that little bike deserved a second life. And so the journey begins.
I completely stripped the motorcycle, powdercoated the frame and al the other bits and bobs, did a top-engine overhaul, resprayed the engine, rebuild the carbs, new tires, new spokes, added a second disc in the front and bought a whole load of new and second hand parts to restore the poor fellow to its former glory.

I am at the point that the bike is almost back together in one piece and so I started on the 'the electric stuff'.
Since the old wiring was completely ruined by alterations by the former owner(s) I bought a new repo wiring harness and replaced the small harness (behind the left sidecover) with a second hand one in better condition. I also updated the ignition with the electrical kind; everything for my precious.

First time i hooked the battery to the system i had the following result:
things that worked:
- headlight (with different settings)
- starter engine
- dashboard with oil pressure light, neutral light, etc.


I checked all the wiring and I saw a few mistakes (the wiring harness is a reproduction with other color cables. There is a colourmapping table delivered with it, but it is still a bit tricky). I fixed the errors and did a second run:
- headlight worked
- dashboard worked
- blinkers worked

So now the starter engine wasn't working. Checked the wiring and thought a I saw one final mistake. Fixed that, connected the battery and turned the key to 'on'; Headlight worked, dashboard worked, blinkers worked.
But as soon as i pressed the starter button, everything went dead and not a single thing has worked since that fatal 'starter button' moment. Not even a satisfying click from the starter selenoid..

I replaced the old rectifier with the modern 2-in-1 kind with cooling fins, replaced the fuses, cleaned out the ignitionswitch (cleaned the copper contacts inside), triple checked the wiring and tested the starter selenoid (clicks when hooked up to the battery).

Now i ran out of ideas and don't know where to look next. Do any of you guys have a clue where to look?

Thanks in advance and any help is very much appreciated.

Greetings,

Martijn

[martijn]

Thanks for the fast reply, i really appreciate it! I have 5 fuses under the LH cover (2 are not wired up so I guess they are spares). I've checked them and they didn't look like they were busted. I've replaced them anyway buy still nothing. The fuses I replaced them with are a tad smaller but they stay in place and have the right ampère (7a and 15a). Is there something I am missing here?

[bryanj]

What electronic ignition did you fit?

[martijn]

So if you turn the key ON, does any electrical light up?

I turn the key and then simply nothing happens. Battery works btw.

[martijn]

What electronic ignition did you fit?

An 'accent electronic'. Bought it of a Honda CB four specialist in the netherlands.

[bryanj]

You need a multimeter set to 20v dc and start with black lead on battery -ve and check every point in loom with red lead for battery voltage to find out where it dissapears

[Bankerdanny]

It is possible that the switch is the issue if it is original. The 550F switch has a known failure point. Do you have a multimeter that you can use to start testing for power at various connections?

[martijn]

Thanks for alle the replies! My multimeter is up for a new battery. Going to get that tommorrow as well as some new fuses (just to be sure). I'll keep you guys posted!

[Kyle2020]

Following. I’m actually having a very similar issue on my bike and can’t figure it out for the life of me

[martijn]

Allright, I've installed new fuses and started to do some measurements with the multimeter.
The setup: black lead of the multimeter on the battery (positive side, the side that also contains the wire that runs to the starter selenoid). Multimeter set to 20 volt (dc)

I started of with holding the red lead on the left starter selenoid bolt (nothing), to the green-red and yellow-red wire coming out of the starter selenoid (nothing). This went on for a while..

After a moment I got a measuring of [0.51] on the red-yellow wire from the starter selenoid. This measurment popped up when the complete fusebox was unhooked. When I re-attached the fusebox I would not get a reading anymore (0.00). 
With the fusebox unhooked i would get a reading of 0.51 on different wires all over the bike.

I checked the fusebox but cant see anything strange about it. The backside (inside) looks really clean and nice. The solders are in nice shape and the wires are in good nick as well. I've also checked the fuses and they are also in working order.

What could this be?

[bryanj]

If you have the - ve of the battery going to the solenoid its wired wrong and your rectifier is now toast

[martijn]

My bad, I did had it wired to the plus side afteral. I mixed it up in my head while writting it down. Fixed the mistake in my earlier post.

Testes my rectifier (Just to be sure), alle tests were positive so it is in good working condition.

[bryanj]

Right so put the black wire from tester to NEGATIVE of battery and use red wire to test for voltage at several points.

It is important you do the tests as asked and do not wander off on a tangent or test something else because you think it might matter, sorry to be rude but long distance electrical testing is difficult and answers need to be exact to the questions asked or they mean nothing

With ignition OFF

Battery
solenoid big wire in
Fuse in
Fuse out
Red at ignition switch

With ignition ON but Kill Switch and lights OFF

Fuse in
Fuse out
black at ignition switch
Black in headlamp shell
Black at regulator

[martijn]

No worries, I can understand this being a bit frustrating so dont worry about it.

This evening I will start checking the system via your list. Thanks again (a lot) and i'll get back to you!

[robvangulik]

Where does your house live in Nederland? If not too far I might be able to help in situ...
And there is a quite active Dutch www.cbfourclub.nl that could be of help too!
And do you have a manual for your bike?

[martijn]

Where does your house live in Nederland? If not too far I might be able to help in situ...
And there is a quite active Dutch www.cbfourclub.nl that could be of help too!
And do you have a manual for your bike?

That would be great actually. I like to learn and maintain it by myself but this is getting a bit frustrating. I live in Deventer and I am actually a member of the cbfourclub. I signed myself up ages ago (even before i had the bike). I have the Haynes cb550f/cb400f manual.

[robvangulik]

Than it would be smart to make better use of that membership!
Activities are slowly starting up again after being postponed in the corona crisis...

[Deltarider]

I have the Haynes cb550f/cb400f manual.

Martijn, some tips. I'd rather consult the source manuals, by Honda.
First verify what model CB550F you have: F, F1 or F2. You can do this by comparing the engine- and framenunber of yours with those listed in the first few pages of the CB550F parts lists. The three CB550F 4-1 Super Sport lists are all here: http://www.honda4fun.com/materiale-documentazione-tecnica/parts-list/parts-list-cb550 Then go here to consult the original Shop Manual CB500-550 (part1-10): http://forums.sohc4.net/index.php/topic,17788.0.html (scroll down). The CB550F addenda and wiring diagrams start at p.153. Realise there are several wiring diagrams. The F2 wiring diagrams are in the very last pages of forsaid Shop manual. Identifying your specific model you do only once. Recommended.

[martijn]

Right so put the black wire from tester to NEGATIVE of battery and use red wire to test for voltage at several points.

It is important you do the tests as asked and do not wander off on a tangent or test something else because you think it might matter, sorry to be rude but long distance electrical testing is difficult and answers need to be exact to the questions asked or they mean nothing

With ignition OFF

Battery
solenoid big wire in
Fuse in
Fuse out
Red at ignition switch

With ignition ON but Kill Switch and lights OFF

Fuse in
Fuse out
black at ignition switch
Black in headlamp shell
Black at regulator

Allright I did the measurements. Just to be sure, during measurements the battery was connected regularly (ground cable connected to negative, cable to selenoid connect to positive side)

With ignition OFF

Battery: 13v
solenoid (wire from positive side of battery): 13V
solenoid (wire from cable from engine): 3v
MAIN Fuse in: 13v
MAIN Fuse out: 13v
TAIL fuse in: 3V
TAIL fuse out: 3v
HEAD fuse in: 3V
HEAD fuse out: 3V
Red at ignition switch: 13v

With ignition ON but Kill Switch and lights OFF

MAIN Fuse in: 13v
MAIN Fuse out: 13v
TAIL fuse in: 3V
TAIL fuse out: 3v
HEAD fuse in: 3V
HEAD fuse out: 3V
black at ignition switch: 3V
Black in headlamp shell: 3V
Black at regulator: 3V

[martijn]

I have the Haynes cb550f/cb400f manual.

Martijn, some tips. I'd rather consult the source manuals, by Honda.
First verify what model CB550F you have: F, F1 or F2. You can do this by comparing the engine- and framenunber of yours with those listed in the first few pages of the CB550F parts lists. The three CB550F 4-1 Super Sport lists are all here: http://www.honda4fun.com/materiale-documentazione-tecnica/parts-list/parts-list-cb550 Then go here to consult the original Shop Manual CB500-550 (part1-10): http://forums.sohc4.net/index.php/topic,17788.0.html (scroll down). The CB550F addenda and wiring diagrams start at p.153. Realise there are several wiring diagrams. The F2 wiring diagrams are in the very last pages of forsaid Shop manual. Identifying your specific model you do only once. Recommended.

Thanks! I'll look into that!

[bryanj]

That prooves your ignition switch is bad and loosing a lot of volts between red and black. You will get nowhere till you replace it and test again

[martijn]

That prooves your ignition switch is bad and loosing a lot of volts between red and black. You will get nowhere till you replace it and test again

Wow thanks! I will sort that out and het a new one! I'll keep you guys posted and the progress.

[Deltarider]

With the IGN switch in ON position, is there a voltage drop between RED and BLACK? If so, contacts are bad. When you have the IGN key switch removed, you can do us a favor and perform the simple test described here:
If you find the voltage drop measurement difficult to do, there's a shortcut*, but - I warn you - it can only give a gross indication and is not as reliable!
*It's ofcourse about the RED and the BLACK wire. Select low Ohms range on your DMM, usually 200. Now first hold the probes firmly against eachother for about ten seconds and wait till the resistance does not further drop. Read the resistance the DMM measures, usually something like 00.3 Ω. Remember it! Now one probe to the RED of the IGN key switch - in ON position - and one to the BLACK. Read the resistance now, subtract the 00.3 Ω or whatever you've found before, when testing the DMM and you'll have the resistance between the contacts in the IGN key switch. Please report back. Note that a resistance measurement is done with NO current, so you need to disconnect the switch from the battery. But again: the voltage drop measurement is the preferred and better method by far.
If you have the time and patience, you could repair the switch. The thread is here: http://forums.sohc4.net/index.php/topic,179776.msg2084881.html#msg2084881

[Deltarider]

Oh, wait a minute, you have the IGN key switch in a different spot. I don't know if you can remove it as easy as mine. Probably not. Sorry.

[bryanj]

Delta, he has already tested red to black and answered and been told get new switch