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All,

The crackomatic coil was indeed causing the no-start condition. I swapped it out with a 0.7 Ohm (Euromotoelectric suggests the 1.5 Ohm would have been just fine too) and it started right up.

I replaced plug wires and caps less than a year ago, so I just swapped those over.

I even pulled one plug at first to confirm spark (which was now much fatter than before), and it tried to start on just the one cylinder.

Thanks for the thoughts! And thanks gspd!

I mentioned earlier that your original coil was 1.5 ohms and that the 0.7 ohm coil wasn't introduced until much later in the 90's together with an ECU that could handle the higher current. The later ECU will probably have variable dwell and auto cut off to protectant itself from overheating.

Unless it's already been replaced with a later type, how do you know that your ECU can handle a 0.7 ohm coil without burning out ?

barryh wrote: ↑Wed Aug 21, 2024 7:10 am I mentioned earlier that your original coil was 1.5 ohms and that the 0.7 ohm coil wasn't introduced until much later in the 90's together with an ECU that could handle the higher current. The later ECU will probably have variable dwell and auto cut off to protectant itself from overheating.

Unless it's already been replaced with a later type, how do you know that your ECU can handle a 0.7 ohm coil without burning out ?

Barry, hopefully someone can provide a more informed answer for you. I simply went by the part supplier’s recommendation: “If you have an Airhead with the transistorized ignition system (post 1981) you would want to use the EnDuraLast 0.7 ohm coil. Although some people choose to use a 1.5 ohm coil, which also seems to work well.”

Your new coil shouldn't be a problem, however, real airhead riders carry a spare ICU.
Less than $40 @EME.
under $10 @ AliExpress, hmmm...gotta try one.
https://www.aliexpress.com/item/1005004 ... ry_from%3A

All those similar modules (BMW VW VOLVO etc) are interchangeable. The older ones ('80's) overheated and failed more frequently than the newer (90's +) ones. Some cold start better than others; this seems more apparent when using the kickstart as certain ICU's make kick-starting virtually impossible. Some have a dedicated tach terminal in addition to the coil negative terminal.