Topic: electrical system in TROUBLE!!!

[jimschnabel]

i have a 1973 cb 500 f.  i got it about three weeks ago, and have been getting back in shape.  i got it running the other day, and it was running great.  then the electrical system shut down and the bike quit running.  someone who had the bike before me has done a lot of d.i.y. fixes, many of which were done incorrectly and/or poorly.  when the bike quit current was sent to ground on the green wire, which as a result melted the insulation off of it from the rectifier all the way up to where it attaches to the frame under the tank.  the fuse never blew, but the fuse holder began to melt because the 20 amp fuse in it was too high a rating (i'm guessing).  can anyone help find a good wiring schematic, and or some tips for my situation.

thanks,
jim

[frostypuck]

I just scanned one for you, email me and I'll email it to you.
Chris in Boston
crismary@yahoo.com

[Bob Wessner]

Chris,

Why not send a copy to Glenn also. He's added some 750 wiring diags. to the site also. It might make a good reference for others who might need it.

[SteveD CB500F]

I've found the Interactive Wiring Diagram on www.oldmanhonda.com to be really helpful in working out just what does what.  Then back to the manual for the details.

[jimschnabel]

thanks for all the help with the wiring diagrams everyone.  i've encountered a new issue now.  i've checked the field coil, and the stator coil both appear to be fine.  i tested them in accordance with info i got from a chilton manual.  the rectifier is however confusing me.  the testing proceedures in the manual were a little confusing.  can anyone out there tell me how i should be using my meter to test the rectifier.  additionally if all of these parts are okay what else could have caused the meltdown i experienced (green ground wire melting off its insulation from the rectifier to where it attaches to the frame under the tank next to the coils)