At this time, the only H-D cylinders we manufacture are for the EVOs. The primary silicon crystals give the hypereutectic aluminum its excellent thermal and wear properties. Diamond tooling is required to machine our cylinders. Conventional cutting tools are impractical. Our alloy has less thermal expansion than a standard cylinder which contributes to keeping the cylinders round and true - virtually distortionless.
Closer clearances guide the piston through the bore with less rocking.
The combination of less rocking and less friction reduces the loads on the crankshaft which increases acceleration, fuel efficiency, and longevity.