Topic: 1-4 coil connected to 2-3 points and vice-versa

[vigiltln]

1971 CB 500 and has been running for the last year.  The 1-4 coil (on the left side) has a yellow wire and is connected to the 2-3 points and vice-versa.  How can it run?  To me it runs good, but this is my first bike and I do not know better.

[bjbuchanan]

It means that they installed the advancer cam backwards and then said screw it and reversed the wires instead of fixing the cam. Could have switched blue to yellow and vice versa at the coils to correct it.

Either way it won't kill the performance or driveability just the "correctness"

Bikes are simple systems that is why it doesn't really screw anything else up, it is just dedicated wires. If you work on newer stuff and cars you know better than to criss cross and mess around unless you really know that wiring diagram

[vigiltln]

Hmmm.  Thought I might have switched yellow to blue when I scrapped the original coils for Dyna 5ohm coils last year.  If I did it would not run, right?

[bjbuchanan]

As long as your stuff is swapped around on both ends it doesn't matter. If you hook them up wrong it won't work. If it works you didn't hook it up "wrong"

[vigiltln]

So for "correctness" I should pull the points plate, remove the spark advancer, rotate the cam 180 degrees and switch the blue and yellow wires so blue is from the 1-4 coil to 1-4 points and yellow from 2-3 coil to 2-3 points?

[bjbuchanan]

Check the wiring first, maybe it got switched up near the oil tank, there is a connection there. Then re-switched up at the coils to make it work. Blue is 1-4, Yellow 2-3