Harley Davidson Shovelhead Hydraulic automatically self adjust Primary Chain Tensioner

York chain tensioner features a hydraulic valve which controls the motion of the submerged piston which constantly keeps the chain in tension.
This chain tensioner improves shifting performance, reduces noise, extends primary chain life, and reduces vibrations caused by the primary chain. Tensioner is designed to automatically self adjust the primary chain tension, even during acceleration and deacceleration. *NOTE: Head of adjustment screw should be 5mm out from body of hydraulic adjuster.

Instructions / Diagrams
FITS    
FXD 1991-2005
FLST 1986-2006
FXST 1984-2006
FL 1965-1984
FX 1971-1984
FLT 1984-2006
FXR 1984-1994