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havent been on here since 2010! wow. well I am pack now and am in need of some help. I have a 1981 honda cb 400 (hawk I believe) and I cant get spark. the bike has not run in 10 years, the carbs have been cleaned, oil has been changed, horn ........... well that still dosnt work.
here is my question. no spark at all when I crank. (full battery) when I put a test light on the signal wires they are hot but do not pulse as I expect them too. to me this sounds like a points or ignition box issue. I am wondering if the bike has points or is it electronic ignition. where are they located and how does a guy check them? could it also be the coil? (doubt it) is there something else I could be missing? thanks in advance for your time.
 

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The bike operates a pointless ignition system i.e. a magnetic pickup located under the LH engine cover. There is a CDI (Capacitor Discharge Ignition) unit which is a 3" x 2" x 1" box mounted on the frame at the front and under the LH side of the tank and two wires from this attach to the coil. No spark on both plugs could be a fault anywhere in the system but in my experience the most likely cause is the simplest.

I think that the bike has a clutch switch (engine will only start with the clutch lever pulled in) which is very exposed and can stick or corrode. Not sure if this interrupts the starter or just the LT side of the spark but it can be easy by-passed to check.

Next is corroded connectors or breaks in the wires to and from the CDI unit to the coils. Also check that all of the grounds are clean and well made in particular check the ground from the green wire under the CDI unit back to the battery. After that it is a case of getting the manual and checking the various voltages to and from the CDI unit.
 
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