Sleeve Fits Mono-Block Cylinder Number 420413041, 420413044 & 420623246 Cylinder sleeves made from centrifugally cast iron alloy. Outside diameter precision centerless ground. Ports cut to precision dimensions and shapes for ease of installation and port match-up. Inside semi-bore diameter must be bored and honed to size piston after installation. Rotax…
Original cylinder bore is alloy chrome plated, nikasil or electrofused. The cyinder must be bored to accept the new cylinder sleeve.