Linn Gear Model: 40B8H
Stock bores of No. 40 sprockets with 23 teeth or more are nominal and must be re-bored even though the bore desired is the same as listed stock bore.
Listed maximum bore is with set screw at angle to keyway. (H) indicates sizes available with or without hardened teeth. All other sizes available with hardened teeth as an alteration.
Hub diameters marked "R" are recessed for chain clearance. Specifications
Length Through Bore
Linn-Gear 40B8H HARDENED SPROCKET H1