Topic: Are my coils bad?

[75 super sport]

I have a 1975 cb750f, was checking for spark today and noticed that the spark is very weak, if there at all. Sometimes a spark will show and sometime it will not. But it is never a strong spark. Any help is appreciated, thanks.

[cmonSTART]

There are a lot of things which can result in weak spark.  It's possible your coils are bad, but you should do a good ignition tune-up first.  Make sure the points are in good shape and properly gapped/timed.  Make sure all the connections are good, battery is charged and all.  Make sure the plugs are good as well as the wire caps. 

You can ohm the primary and secondary windings in the coils to test them.  I'm sure the book values are somewhere on this site.  A dead giveaway your coils are bad would be either a shorted or broken reading.  Like I said though, focus on the other stuff first unless there is an obvious defect with the coils themselves. 

[75 super sport]

How do i gap the points? And how can i do a timing test with out a light?

[cmonSTART]

Without a light it can be done by static timing, which only requires a circuit tester or multi-meter.  A service manual will detail the procedure for gapping and timing. 

Somewhere on this site is a great collection of Honda service manuals.  Hopefully someone will jump in here with the link.  Or you could go purchase a Clymer manual which will work.