uh uhIts nickel plating. Works good on two cycle engines.
Nickle - Silicon
Nikasil is short for nickel silicon carbide. Silicon carbide is a very hard ceramic (much harder than steel) that can be dissolved in nickel. The nickel silicon carbide solution can then be electroplated onto the aluminium cylinder bore. After the cylinders are plated, the Nikasil bores are diamond honed to a plateau finish. Pistons will need to be fitted with Nikasil compatible piston rings as chrome rings commonly used with cast iron bores are not compatible.
Nikasil - Wikipedia
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