Topic: Main fuse blowing. Any help appreciated.

[jacksonrpower]

Hello, I was blowing fuses when I turned the ignition key and suspected it was the kill switch, so I unplugged every wire associated with the kill switch and now I can turn the key on and all the lights work and the fuse isn't blowing, but when I bridge the starter solenoid with a screwdriver the fuse blows. Any insights on what/where my short might be? It's a 1972 CB500 with a 1976 CB550 engine.

[Black 750K8]

Are you sure when you bridge the sol. that you are not touching the tool or what ever you are using to ground.

[Black 750K8]

Also the kill sw. has nothing to do with any lights all it does is break power to the coils.

[jacksonrpower]

Not exactly sure, maybe. I may plug the starter button back in and try to use it instead of bridging the solenoid. Yeah I know that, but when I unplugged the kill switch the fuse stopped blowing instantly when I turned the key on. 

[jonda500]

The black/white killswitch/coil power wire might be shorting out due to the switchblock crimping the wires againt the handlebar and cutting into the insulation?
As to why bridging the solenoid blows the fuse (seems like a seperate issue) I haven't encountered that one but surely someone out there has? 

[Hastenbrucke]

Had the same problem with my 750 K3 ...I did the usual checks on the all the switches etc. It was the fuse holder.
The blades although looking clean were not and used HONDAMAN'S advice and cleaned them up. In the end they had deteriorated so much that I switched it out and wired in a blade fuse with a waterproof connector cover. New indicator relay as well and NO MORE ISSUES. I was amazed that slightly dirty connections on the old rubber fuse holder would build up that much resistance and then heat and blown fuse.
In the end I couldn't give in to new technologies and found a new fuse holder from Yamiya ....ORIGINAL Honda ...it has gone back in.
Don't know if this is your problem but I would check and clean and replace there first.

[jacksonrpower]

I'm sure something is going on inside the switch housing. Yeah it probably is a separate issue. It is a brand new fuse holder.