Cylinder Sleeves
A cylinder sleeve lets you save a scored, seized or worn-out cylinder instead of replacing it. The plated bore (NiCaSil, chrome, electrofused or boron composite) is machined out, the iron sleeve is pressed in, and the new bore is then finished to your piston. Most of this page is LA Sleeve snowmobile sleeves; ProX covers two personal-watercraft engines (Kawasaki JS750SX '93–95 and Sea-Doo 720 '95–05).
How LA Sleeve sleeves are made. They are centrifugally cast from a carbon-chrome-molybdenum alloy at about 200 Brinell, the outside diameter is centerless-ground for a consistent press fit, and the intake, exhaust and transfer ports are cut to shape so port match-up at installation is straightforward.
Pick by FL number, not by bore alone. Each LA Sleeve part number is cut for one engine family's port layout and stock bore (for example FL1252 is listed at a 67.50 mm standard bore for a 700 cc twin). Open the product page and check the stock bore and displacement against your engine before ordering; a sleeve with the wrong port timing will not run right even if the bore is close.
Plan the machine work. A sleeve is not a drop-in part: the cylinder must be bored to accept it, and the sleeve's inside diameter is supplied undersize so it can be bored and honed to the exact piston you will run. Order the piston and rings first, give the sleeve and piston to the machine shop together, and finish with a top end gasket kit. If the cylinder casting itself is cracked, a complete cylinder is the better route.
Free shipping on orders $50+ (Lower 48).
