It seems that besides being a tinker, Mark Walker is a thinker as well.
A long existing problem / drawback of the “Cross floating cylinder design” is how to support the cylinder head on the crankcase and how to receive the thrust loads the piston skirt applies onto the floating cylinder.
With the cylinder head supported on some long stands, things get difficult.
Mark Walker thought a solution: to bridge the two cylinder heads of his Big Ned engine (a V-2 at 90 degrees with Cross rotary valves and floating cylinders) to form a stiff triangle structure.
With the added bridge (the gray pipes from the one cylinder head to the other):
each cylinder head is not left alone to vibrate, and the stands can be thinner.
It takes more than a tinker to make from scratch, with limited resources, a competitive drag racing engine / motorcycle:
Pistons and Rods under Development.
The first Crankshaft was made from Assab Steel. It was 4" Stroke. It had Press in Main Shafts to Flywheel and a Screw up Crankpin with 2 different numbers on threads on each end of the Pin and a 2" Big end Sleeve. The first Barrels were machined from a Caterpiller Liner
Cylinder Heads, Conrod, Slipper Piston- machined from 5083 running on teflon buttons, Aluminium Bronze Seats, Stainless Steel Valves, Heads Machined out of 5083, Conrods - 1 in construction due to a backfire cracked the rod - machined from 7075 plate.
And as he says:
“I have spent my life working on, modifying and building Poppet Valve engines and then converted over to a new religion… “Rotary Valves”
When you realise the advantages of a Rotary Valve over a Poppet Valve are staggering…. They are an addiction.