Abstract: A method of retrofitting a V-twin engine for increasing displacement. A cylinder replacement is performed by dismounting each of a pair of original cylinders from a crankcase. A pair of replacement cylinders are provided, each having a second cylinder bore diameter larger than a first cylinder bore diameter of the original cylinder to provide the V-twin engine with a second displacement greater than a first displacement of the original cylinder. A replacement spigot portion from each of the pair of replacement cylinders are aligned with a respective bore of the crankcase. The replacement spigot portion includes a second outer diameter larger than a first outer diameter of an original spigot portion. The second outer diameter of the replacement spigot portion and the crankcase bore diameter defining a subsequent diametric clearance smaller than an original diametric clearance of the original cylinders.

Abstract: A cylinder for a V-twin engine includes a section of steel tubing cut to a length. The section of steel tubing includes a first portion having a first wall thickness and a second portion having a second wall thickness less than the first wall thickness. The second wall thickness is less than 0.050 inch. The section of steel tubing includes a first ribbing pattern on an outer surface, within the first portion, and a second ribbing pattern including multiple ribs formed on individual ribs of the first ribbing pattern. A cast body is provided on the first portion of the section of steel tubing so that the section of steel tubing is fixedly secured within the body to form a cylinder sleeve defining a cylinder bore. The second portion having the second wall thickness extends from an end of the body to be received within a bore of a crankcase.

Abstract: A cylinder for a V-twin engine including a body with a first end having a surface configured to mate with a cylinder head, and a second end configured to mate with a crankcase. A sleeve is fixedly secured within the body to define a cylinder bore. The sleeve includes a first portion that extends from the first end of the body to the second end of the body. The first portion of the sleeve has a first wall thickness. The sleeve further includes a second portion that extends out of the second end of the body to be received within a crankcase bore. The second portion has a second wall thickness that is thinner than the first wall thickness. The sleeve is constructed from a chromoly steel alloy material, and the second wall thickness is less than 0.060 inch.

Abstract: A cylinder for a V-twin engine includes a section of steel tubing cut to a length. The section of steel tubing includes a first portion having a first wall thickness and a second portion having a second wall thickness less than the first wall thickness. The second wall thickness is less than 0.050 inch. The section of steel tubing includes a first ribbing pattern on an outer surface, within the first portion, and a second ribbing pattern including multiple ribs formed on individual ribs of the first ribbing pattern. A cast body is provided on the first portion of the section of steel tubing so that the section of steel tubing is fixedly secured within the body to form a cylinder sleeve defining a cylinder bore. The second portion having the second wall thickness extends from an end of the body to be received within a bore of a crankcase.

Abstract: A cylinder for a V-twin engine including a body with a first end having a surface configured to mate with a cylinder head, and a second end configured to mate with a crankcase. A sleeve is fixedly secured within the body to define a cylinder bore. The sleeve includes a first portion that extends from the first end of the body to the second end of the body. The first portion of the sleeve has a first wall thickness. The sleeve further includes a second portion that extends out of the second end of the body to be received within a crankcase bore. The second portion has a second wall thickness that is thinner than the first wall thickness. The sleeve is constructed from a chromoly steel alloy material, and the second wall thickness is less than 0.060 inch.