no spark

My 1982 KZ305 developed a rough idle. I placed a timing light on each wire. One had the light flickering as it should . The other had no light. I went to coil of the no light wire and had 11.5 volts with ignition just in the on position. Same with the good wire's coil. Placed contacts on inside of wire that hooks to spark plug and also had 11.5 Volts! Went to the good wire and had the same reading. How can I have voltage and then no spark when turn engine on on that one wire?

Check to see if the spark plug is fouled. Ed

There's a 5000 ohm resistor inside the sparkplug cap that may be comming intermittent.To check, unscrew the sparkplug cap from the sparkplug wire, and using a multimeter, set it up so the meter is in OHMS(looks like an upside down horseshoe Omega) range of 20K. Put the RED probe where the sparkplug would fit, and the other BLACK probe where the cap screwed onto the sparkplug wire.

If your meter has several sockets for the test leads, you're going to plug into COM (Common) for the BLACK test lead, and the RED lead will plug into the V and OHM socket.

If the sparkplug cap is good, you'll see resistance.

Bad wire, Bad cap, or bad plug. Wouldn't hurt to replace the coil and wires, new plugs. Probably run sweet.

Would clean the points contacts and set the gaps.

The closed points allow the small wire from the ignition coil to reach ground, which charges the coil.

Opening of the points is the event that causes the coil to fire by un-grounding the coil.

The above presupposes that the other small wire to the coils is furnishing adequate full battery voltage to the coils (perhaps a red wire or a red/yellow wire).

Good Fortune!

MFOLKS, I did what you suggested and found a bad end. I had already cleaned and adjusted points as well as as my plugs, which were only a couple of months old. If I flexed the end a bit , my meter would show resistance but when I let it go back to normal, none showed. Double checked my results on my good wire and had resistance as soon as I made my connections !!! So now I will go to my KAWA dealer and grab a new end and see if my troubles disappear. Thanks for the tip !!!!

A nice, simple fix!