Buell Xl , black replacement cylinder ( x1 ) 

with late style bigger cooling fins ( 04-21 XL / XB ) for better cooling

sold a piece, 

need to be honed to piston size 

Stock replacement aluminum cylinder with cast iron liner. Stock 3-1/2" bore. Stock 4.650" length. Repl. 16469-10. Note: Cylinders must be finish bored and honed to fit stock size pistons. Cylinders are sold without pistons and rings.