GZR OEM Inline Crankcase Only PDF Print $249.00 GZR Inline billet crankcase "bare" Add to Wishlist Add to Compare Back to: GZR / Rcmk Inline Engines and parts Description GZR Inline Billet crankcase "bare" This is a bare case either rebuild your old motor or transfer over your old parts to this Brand new Billet crankcase. RCMK S-520 internal parts are interchangable with this crankcase.