A good arrangement on a Super Rocket is to retain the original magneto with manual advance & retard and to fit also an automatic ATD. Normally, with this arrangement, you would leave the handlebar lever in the full advance position at all times. When Super Rockets were new 101 octane fuel or higher was readily available at the pumps and it contained lead. This is what prevented knocking / pinking which often occurs when an engine is under load. If your Super Rocket has an ATD it will do all the usual timing adjustments you need, i.e retarding at tickover and at startup and will go to full advance as the revs rise but, once on full advance, cannot do anything about pinking under load maybe when you hit a hill or decide to give it fistfull. A manual arrangement provides a sort of ATD overide which enables you to retard the timing by way of the handlebar lever when under load with cr4p fuel if the bike pinks.
