Blowing main fuse

Quick question. I have a '80 kz1000 classic (EFI).

Can a loose spark plug cap cause a main fuse to blow?

I changed out the plug the other day and in putting the wires back on, I pulled the cap off #4. I noticed it was not a really snug fit. Then I went out riding. About 5 miles from the house, it sounded like it was missing on 1 of the cylinders, then died.

Luckily I had a spare fuse. But it started to melt the fuse holder in the fuse box.

Today I spent about 2 hours with the tank off looking at all the wiring and I couldn't see any other obvious problems.

I am also using a vetter, but that wiring seems to check out too.

Any thoughts? Anyone?

Thanks:)

i wouldnt think a plug wire being off would cause that;)

Did you have the tank off when changing the plugs?? If start to check there.Also do you have the OEM glass fuses?? The clips that hold the fuses lose there tension and if it is loose it will cause heat from to much resistance causing it to get hot melting and mpossibly blow the fuse.

The main fuse is fed by the white or white/red wire off your reg/rec and then goes to the ignition switch via a white wire where the switch essentially turns the power into various subcircuits that are fused as well. One of the downsides to the Kaw electrical system is that if a subcircuit has a problem (short), it usually ends up blowing the main fuse making fault finding of a short much more difficult. I doubt the loose plug wire was the culprit and as has been pointed out, moving your tank likely is the culprit. The short is likely under the tank and likely involves the main harness but could be in any of the wires that go to the switchgear or into the headlight or a bad connection or bare wire anywhere under there.