Re: 78 cb750K won't fire up. (1 coil fires other doesn't)

Posted by mitchberry on Sep 07, 2010; 4:41am
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/78-cb750K-won-t-fire-up-1-coil-fires-other-doesn-t-tp1425305p1430559.html

Cool man thanks for the input.. as for the coils I know for sure they both
work.. the problem is the point on the upper left not getting power to trip the
condenser to spark the coil and plug... not sure why.. even ran a completely new
wire. The weird thing is that I can't for the life of me figure out where the heck
the electricity comes from....  the wire goes from the point to the coil...
nothing is power in... maybe the power switch somehow? I have no idea what gives the blue wire electricity....  i do know though that the black wire is supposed to complete a circuit with the black and white wire through use of the off on off switch, though it wasn't so i ended up having to bridge it with a piece of wire... i then took the wire out, put a piece of solder on the bottom of the place where the two wires were soldered to the switch (which didn't seem to work)...  

maybe having to jerry rig the bad off on off switch is what's causing all of this?????  damn.. maybe i should just... replace ALL of the wiring, coils, switches, and whatever other electrical crap i can find on this bike...  looks like i will end up doing so before diagnosing this problem....
 
I think if I knew how the blue and yellow wires actually GOT their power, I could find my problem.....

As for the oil light, I had the tail light unplugged.. I did plug it in but the
oil light is still on.. worth a shot anyhow.. with that said the rear brake
doesn't trigger the brake light.. either THAT switch is bad too, or wired incorrectly (still).. or
maybe that filament is burned in the bulb..  

Maybe if I fix that the light will go off... or maybe I have a faulty oil
switch...

Are you sure the oil switch won't keep it from running? Where is the sensor
physically on the sohc motors? i'd like to try to bypass it temporarily to see if that helps anything.  of course i don't want to run it much until i know for sure that i'm not actually minus oil pressure..


I dunno... maybe I just need new points or something.. I don't know if the kid
tried to adjust them. All of this effort and maybe its just not connecting when the cam spins past it.
 
Though there's still no juice to the point itself so idk.. actually there is, but it's like half a volt. Either way I found tonsssssss of stuff that I had to fix and am still finding things like the
fact he had the shop put a -used- radial tire on the front wheel backwards...

fortunately ill be buying new ones, but that's a SERIOUSLY UNSAFE no no...