Topic: Electrical Issues - 1978 CB550K

[rbswang]

First off, I can kick start the bike and ride it all over the place but the button start does not work. It did work last season, but after winter storage, I no longer get a response when I push the button. Which part of the electrical system would I need to replace for the button start to work?

Second, I blow a lot of the main 15A fuses while kick starting the bike. I also noticed this fuse gets extremely hot and often needs to be jiggled for the oil/neutral lights to go on. Should a new fuse panel solve some of these issues or is it most likely a deeper issue?

Thanks in advance!

[cben750f0]

sounds like a short some where or  a corroded connection, get a wireing diagram, and trace the wires to the sarter, and neutral light, good luck

[CHUNG]

There seems to be an issue with those bikes. The ground might to be the fault although I have only looked at bout 5 bikes, from the first to the last.... that had melted harnesses. They all share a common item, (if I remember correctly) a single ground on the main harness near the IGN coils. If this ground were to become faulty, it might be the cause for the wires melting because most of the current then has to ground all the way back throuh the single wire rather than through the frame? I have a pretty cherry harness for a 78 550F. The only flaw is some overheating on a short portion of the harness leaning from/to the above mentioned grounding lug. I haven't made the (slight) repair but it has led to to concentrate on that as the possible problem for the total meltdowns that I have seen so far? Three of the bikes were of the earliest models.

[Glenn Stauffer]

Second, I blow a lot of the main 15A fuses while kick starting the bike. I also noticed this fuse gets extremely hot and often needs to be jiggled for the oil/neutral lights to go on. Should a new fuse panel solve some of these issues or is it most likely a deeper issue?

This used to happen to my 550 lots.  The fuses wouldn't actually blow - the solder would melt out of the upper endcap.  What solved it for me was to clean the corrosion from the fuse contacts.  The heat in the fuse means that there is resistence in the fuse connection.

As for your starter problem, sounds like your starter button might have broken.  It is pretty easy to take the handlebar switch cluster apart and check that things are OK in there.  If they are, then trace the rest of the starter circuit to find the fault.  If the switch is broken and you can't easily find a replacement, you can get a 12volt button switch, run the wires to it,  and attach it somewhere convenient on your bike.

--Glenn

[cben750f0]

i had a similar problem with melting solder, but the heat melted my fuse box ... i ended up removeing the wires and refitting them to a blade type fuse holder... this change also made the bike start easier, so am thinking that my old fuse box was a real electrical resistor in the set up.... that and water in the front junction box of the F1... stupid place to put a electrical box... .. if you like can post a pic of the new fuse box, and how it looks... peace..