First all aluminum cylinder bore
In the beginning pistons and cylinders were made out of steel. Then it was realized that an aluminum piston is a better choice because it weighs less.
The aluminum piston and steel cylinder is still the most popular engine design today.
However, in the last decade the quest for lighter and more powerful engines, manufacturers have been switching to aluminum cylinders that are coated with a thin material of a harder substance.
Which company in the mid 1960s sold a production motorcycle with an aluminum cylinder bore that was coated with chrome?
What is the year, make, and model of this advanced motorcycle?