Quote Originally Posted by DeanFHobart View Post
I remember the ‘two set of pipes motors’... one set of pipes for acceleration and one set of pipes for top end... and there was a solenoid operated valve that would switch between the two sets. Who could compete with that? Not many!!!
Well Dean, it is fun to have you remember being there for the diverter valved Anzani operation. I actually was not around when the -A- Anzani was run for record, either kilo or L. Lawrence, even though I helped with the development & pipe building at times. All of the initial valved pipes on the little motorcycles were operated by a thumb lever on the left handlebar.

I do not recall the actuating mechanism for the valves on the -A- motor in 1966 since it never came out of the trailer at those two Nationals, DePue & Midland. There is a vague memory of Walin & Hallum in an earlier year discussing the upcoming need to add the valve movement to the hand throttle in some way. The first thoughts were to follow what had worked on the motorcycles but I do not know if the electrical method was the final outcome.

As for the Anzani pipe operating range, I think the open megaphone "tuned in" about 6500-7000 rpm and the bounce pipe was set to start at about 8500-9000 rpm. The operating overlap was more than 1000 rpm. The little motorcycles, using two bounce pipes had a larger practical overlap range. Really hard to remember those detail but I know it was sure fun to ride the motos with a simple thumb press giving a repeat boost just as strong as the initial boost at lower speed.
Russ R.