Patent ID: 7627949

Claim:
A method for increasing a displacement of a motor cycle engine comprising a crankcase, a crankshaft rotatably mounted in the crankcase, a first cylinder block connected to the crankcase and defining a first cylinder bore extending therethrough from one end thereof facing a cylinder head to another end thereof facing the crankcase, and a first piston disposed in the cylinder bore and connected to the crankshaft through a connecting rod, the first piston being configured to reciprocate between a top dead center and a bottom dead center, and the first cylinder block having a bottom end received in the crankcase such that the bottom end of the first cylinder block is located below a top end of the crankcase when the first cylinder block is mounted on the crankcase, said method comprising: dismounting the first cylinder block from the crankcase, including removing the bottom end of the first cylinder block from its location in the crankcase; dismounting the first piston from the connecting rod; mounting a second piston having a greater diameter than the first piston to the connecting rod; and mounting a second cylinder block defining a second cylinder bore having a greater diameter than the first cylinder bore on the crankcase, with the second piston received in the second cylinder bore, said second cylinder block having a bottom end which is located above a top end of the crankcase with the second cylinder block mounted on the crankcase, said second piston being configured to reciprocate between said top dead center and bottom dead center and having a bottom end located above the top end of the crankcase when the second piston is at the bottom dead center.