550k3 fuse box?

[3scs]

Can anyone tell me how many fuses should a 550k3 have mine has four in use and one spare took bike  out for the first time had it running in the garage no problems about 50 yards down the road it cut out no electrics checked over found 15A fuse had blown replaced fuse up and running again found fuse was blowing only when lights were on,all wiring diagrams I can find show only three fuses

[hairygit]

If it looks like this picture, which it should do, only 3 are in use, 2 are spares. [ Guests cannot view attachments ]   The fuse blowing is normally down to dirty fuseholders, which should be clean and bright, or dirty connectors in the block plug where it joins the loom. You need to make sure the the brass connectors in both parts of the plug are clean and bright as well. Dirty connections increase resistance, which in turn increases electrical load, which blows the fuse.

[3scs]

Thanks for that it even says sp7 on the first fuse and sp15 on the last one the fuse box and terminals to it are spotless so will check the rest of  the harness

[hairygit]

Next place to look I would suggest is the plug that goes into the ignition switch.

[3scs]

Ok will check that

[matthewmosse]

Also look under the tank, I had the loom rubbed through its insulation by the bottom of the petrol tank once.

[3scs]

Had another look and found I have no positive feed to the 7a head light fuse abit of history on the bike it was made up of various parts off I think a 550f it had a light/ starter switch which had no kill switch on it as was pointed out when I put a picture on here Trigger found me the correct switch which I fitted and all seemed ok but I had obviously wired the headlight into the wrong circuit as it was running off the main fuse I’ve studied the wiring diagram there’s a bl/r to fuse and right hand switch and a bl/y which goes to left hand dip and main what I can’t quite work out where does the +supply come from any advise appreciated Si

[Bryanj]

Inside the RH switch the black should connect to the black/red when lights turned on

[3scs]

So on further inspection I’ve found the 7a lighting fuse is only live when lights are switched on so all is ok with that circuit I’ve checked wiring earths all seem ok I also found headlight bulb was 55/60w should be 40/50w I replaced it with a 35/35w which has improved the problem but the main 15 amp fuse is still getting hot is this normal if you turn the kill switch off it cools down

[Seabeowner]

A 15A fuse carrying say 13A should not really get hot. It is not carrying >15A otherwise it would blow. The source of the heat is the connections between fuse and fuse holder. (or sometimes the soldered joint at the rear). A poor connection = voltage drop. Volts x your current flow = heat. Common problem on these fuse boxes (often seen melted) and often replaced with blade fuses.
Cleaning connections etc may help, or I swapped solder connection on back to one of the spare positions.