Originally Posted by GAS GUY
When you crank the bike does your tachometer needle on your dash work ?
Because the wire from the cdi that pulses the coil also feeds the tach signal, so if your tach is working when your cranking you more than likely are getting your 12 volt pulse at the coil.
DirtyDog has a GENERATION 1 KLR650, GAS GUY, with a CDI igntion. The primary ignition coil windings of the Generation 1 bikes are pulsed with considerably more voltage than the 12 volts you suggest.
The Generation 1 CDI's are powered from alternating current from the stator exciter coil; this AC is stepped up to maybe 100 volts or so inside the CDI (the "igniter" component), this voltage is rectified, and used to charge a capacitor.
When the timing mass on the rotor passes proximate to the pickup coil, a thyristor discharges the capacitor's 100 or so volts through the ignition coil's primary windings; this voltage is transformed many times higher by induction through the ignition coil's secondary windings, firing the spark plug.
The Generation 2 ignition, by contrast, saturates the ignition coil primary windings with 12 VDC; interruption of this current induces a high voltage in the igntion coil secondary windings from the collaps of the electromagnetic field created by the saturation.
More simply put, Generation 1 KLRs have Capacitive Discharge Ignitions; Generation 2 KLRs have Inductive Discharge Ignitions, "fully-transistorized breakerless ignitions," as Kawasaki marketing prose would have it.