I was trying to track down a problem starting my CT3.  The problem started after I swapped carbs but was not resolved by swapping them back.

In desperation I swapped out my ignition coil, an Hitachi CM61-20 for a coil used by many other Yamahas, including my 80cc Chappy, a Mitsubishi F6T401.

The starting issue didn't improve or worsen. It did, however, spark some curiosity about whether I should have even tried the Mitsubishi coil. Are the two equivalent enough that they are interchangeable on a CT3?

thanks,
Rob

If I can be dumb as my old grey mules… tail light..
Wasn’t Mitsubishi the ones that perfected these type of systems for aircraft?
Sneezles61

I believe there are only two methods Yamaha used for spark 50 years ago, prior to their getting into electronics
 1) 12 volt DC battery to a coil
  2) primary AC coil on the flywheel generating 50? AC volts to a secondary coil each time you kick it over
 CT uses method two so any coil designed for similar setup would likely produce a spark.
 
 
 
 

I once used a coil for a much later model YZ80 on a 74 360. Worked flawlessly. You may have problems trying to use an inductive type coil with CDI system or vice versa.