I've mulled this myself. Only thing I can think of is time,
as it relates to the points operating. The electronic triggers, light
or magnetic, are faster. So, lets say it takes 1/10th of a second to
open the points... it is much faster than that, I hope....that
almost-fixed amount of time becomes a greater percentage of the time
it takes for 1 rotation of the shaft. So, the faster the rotation,
higher RPM, the advance number will be different as the time it takes
for the points to open, and the coil collapsing is greater
proportionally than with an almost instantaneous electronically
I hope I expressed that correctly. I'm sure an engineer will
correct me. I know the rocket scientist is off-list at present ;-)
Ciao Peter C.
At 05:49 PM 12/27/2005, you wrote:
> with only one or two degrees difference MAX, why not just spin
> the dizzy a couple of degrees and be done?
> my real curiosity isn't in all the TECH, of setting up on a
> dyno, etc, etc, but what if anything need be done with a stock
> dizzy,(without changing springs, weights, etc)
> BUT more importantly, WHY is the advance changed just by
> getting rid of the points? the rotational mass of the shaft
> hasn't changed all that much by adding a plastic shutter wheel
> to the shaft.