I'm new to this forum. After owning my '71 CB750 for 44 years, I believe my choppy engine operation around 2500-3500 rpm, is actually due to weak spark advance springs. tried different things over the years; but never addressed those springs. has anyone had satisfaction with the DYNA 2000; since it eliminates need for stock advance unit? In 1982, I went with 836 kit, Megacycle cam, and 29mm Mikunis; and it always loves 9-10,000 rpm, but never smooth under 4000. tried a Pamco unit and new coils; but no improvement. (that still utilizes stock advancer)