Piston controlled by Pivot bearings. In order to convert combustion pressure into torque, the piston slides within the cylinder restrained and supported by it's skirt. The clearance required for expansion makes it possible for the piston to rock and slap in the cylinder, causing the compression seals (rings) to become unseated from the surface of the cylinder. With the Pivotal Piston fully under control there is no more piston rock or slap and the compression seals are always held at a normal orientation to the chamber walls. This improves the compression sealing and extends the sealing life. The Pivotal Piston is restrained by pivot bearings and it is now possible to allow sufficient clearance for piston expansion to remove the risk of seizure, without incurring damage during cold running. As the Pivotal Piston no longer acts as a bearing, the friction between the piston and cylinder is greatly reduced. This also leads to an increased service life and a considerable reduction in lubrication requirements. « Back ::

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