Gonzo gn250 boxes on a 85 VT500

[ckahleer]

Will the gonzo box work on any CDI motorcycle?
I want a backup box for my shadow, but whats out there is pricy. would getting a box for each cylinder work, if I make up a 2 into 1 pigtail?

 

[jetmechmarty]

Gonzo box is TCI.

 

[ckahleer]

The terminology is confusing. The sellers on E-bay and Amazon are listing gn250 boxes as CDI. Some call it ECU. Partzilla just calls it an igniter. I don't see any listed as TCI. Its all alphabet soup to me. So, XS650 and GN250 are TCI and VT500 is CDI (at least Partzilla says it is). The VT500 shop manual calls it a transistorized ignition system and spark unit.

 

[Jim]

The terminology is confusing. The sellers on E-bay and Amazon are listing gn250 boxes as CDI. Some call it ECU. Partzilla just calls it an igniter. I don't see any listed as TCI. Its all alphabet soup to me. So, XS650 and GN250 are TCI and VT500 is CDI (at least Partzilla says it is). The VT500 shop manual calls it a transistorized ignition system and spark unit.

A TCI (Transistor Controlled Ignition) is an inductive discharge ignition system. Induction in this case simply means the coil is charged and discharged through induction. The coil primary is charged during it's dwell period and then that discharges across the secondary, creating the spark at the plug.

A CDI (Capacitive Discharge Ignition) has no dwell. It uses a capacitor that is constantly charging. At the "fire" signal, all that energy is discharged through a coil and sparks the plug. Since the CDI has no dwell to worry about, you get accurate ignition timing even when revving to a gazillion rpm. There's prolly other advantages too... that's the only one that stick in my mind though.

Edit: The CDI also gives a fatter, more powerful spark also.