For example, what seals the piston inside the cylinders? That piston must have perfect alignment as it enters the cylinder and contend with side scuffing and maintaining inline position until it leaves the cylinder. What is a tiny bit of wear going to do to the fit?
They address that in two ways it appears.
There are no angular forces pushing the piston against the cylinder walls eliminating the frictional losses of crankshaft engines. The compression/combustion forces are directly in line with the piston/cylinder centerlines. (See illustration “A”)In the CC Engine there is clearance between the cylinder wall and the piston to allow for any thermal changes and component wear, there is no lubrication needed on the cylinder walls. The piston-cylinder pressure seal is in a cartridge located at the entry of the cylinder and allowed to float within the limits of piston-cylinder clearance.