Follow up test with a CDI ignition

Turk,
Not trying to be argumenative, but offering a possible reason for the retardation. Timing lights typically use a Xenon lamp, not sure of the light source in your m/c. Either type, a certain amount of time is reqd for the lamps to come on [ illuminate ]. The crank does twice as many rotations at 6k compared to 3k. But the time period for the light to illuminate does not change with rpm. At 6k, the crank has rotated further before the timing light comes on...& shows up as retarded ign. So is the 'retard' [ or some of it ] the light playing 'catch up' because of increasing rpm?