4th Generation we call the "Good Boy" HP CDI & Magneto

Grubee Inc


Due to extremely short supply only one Good Boy Magneto Coil and CDI per customer. 

In proven lab test the new "Good Boy" CDI & Magneto Coil produces a whopping 5KV more available voltage than the "Old Dad", "Old Son" and the "Fat Boy" magneto coils.   

Check out the attached magneto coil history picture from 2000 to 2021

The "Good Boy & Red Wire CDI  can jump a 3/4" air gap as compared to a 3/8" to 1/2" gap for the stock standard "Old Dad" , Old Son and Fat Boy versions.  OK! How so?

  • The "Good Boy" 488 ohm magneto coil has more turns of fine wire as compared to the so called "Fat Boy" 357 ohm coil that has larger dia. wire.    

  • Good Boy fine wire coil ohm resistance is 485 to 492 OHMs @ 80 degrees F measured with a quality digital ohm meter. 

  • It is a proven fact that the "Fat Boy" coil with a bigger winding dia. and measuring 330 to 357 ohms resistance does not produce any higher KV output than a standard smaller diameter coil "Old Boy" with same amount of ohms resistance.    

  • The CDI with the Red spark plug wire has a larger Micro Farad Capacitor to take advantage of the increased voltage (400 V ) sent out by the "Good Boy" coil.    

  • The "Good Boy" magneto coil is identified by the red spool and has a date of manufacture sticker.  The CDI is identified by the red terminal wire and Red boot. 

  • NOTE:    The CDI terminal fits the spark plug when the screw cap is removed.      See picture.

  • KV = Kilo Volts.   1KV = 1000 Volts.