The old HD and Triumph ignition systems were not necessarily inferior, but they were really easy to modify. For example, you could get a few hundred more RPMs by simply closing up the points gap to .012 - .014 to increase the dwell angle. It was also fairly easy to modify the '58 - 60 something dual point ignition to a dual fire setup, halving the load on the coils and doubling the dwell time.
There is a guy in (I think) Sweden named Jojji who has hacked into the programming on the ignitor to enhance his drag bikes. Unfortunately for the rest of the world, he won't rework them for other people because of liability issues.
One thing that can be done, but is rather complicated, is to modify the timing lugs on the alternator rotor so that 2 pickups can be used along with 2 ignitors. One of the problems with the 720 degree engines is that the coils are fired twice per revolution as compared to once on the 360 engine. This means that even the best of coils will run out of energy near the present redline.
So it is possible to greatly improve the ignition beyond better coils, wires and sparkplugs, but it involves a lot of work.
1. Hack into the ignitor programming to change the rev limit count and advance curve tables on 2 ignitors.
2. Find a place to mount the second ignitor and change the wiring to connect each to just one coil.
3. Make room in the engine side cover to mount a second timing sensor and mount one.
4. Modify the alternator rotor to trip each ignitor once per revolution. Both timing lugs will have to be shortened, one on the outside and the other on the inside to trip only one of the sensors. The outer lug may have to be extended, depending on how the mounting of the second sensor works out. An alternative is to remove the second lug altogether and mount the second sensor exactly 90 degrees off from the original. This will require a serious modification to the cases to provide a place to mount it.
Another possibility would be to design up an entirely new ignitor that starts out firing both cylinders together like the stock one. It would then count out the timing difference between each timing pulse until it can be certain which is left and right, then switch to a single fire mode. Add in a set of advance curves addressed according to RPM and TPS reading. Or else use a very fast processor that can calculate the advance delays directly without using lookup tables.
So, as you can see, the new ignition system can be greatly improved, it's just not all that easy.
