Multiple cylinder engine

An internal combustion engine comprising:

• a first piston reciprocatingly disposed in a first cylinder;
• a second piston reciprocatingly disposed in a second cylinder, the second piston having a diameter less than a diameter of the first piston, wherein the second piston is disposed vertically above the first piston during operation;
• a crankshaft coupled with the first piston and the second piston for rotational motion associated with reciprocating movement of at least one of the first piston and the second piston, wherein the first piston and the second piston are coupled with the crankshaft in substantially the same rotational orientation, the crankshaft configured to be disposed in a generally vertical orientation during operation;
• a combustion chamber fluidly coupled with the first cylinder and the second cylinder to continuously define a fluid volume including the combustion chamber, the first cylinder, and the second cylinder;
• an ignition source at least partially disposed within the combustion chamber;
• an intake valve providing selective fluid communication between an intake system and the combustion chamber;
• and
• an exhaust valve providing selective fluid communication between an exhaust system and the combustion chamber.

An internal combustion engine comprising:

• a first piston reciprocatingly disposed in a first cylinder, the first cylinder having a first diameter;
• a second piston reciprocatingly disposed in a second cylinder, the second cylinder having a second diameter that is substantially the same as the first diameter;
• a crankshaft coupled with the first piston and the second piston for rotational motion associated with reciprocating movement of at least one of the first piston and the second piston, wherein the first piston and the second piston are coupled with the crankshaft in substantially the same rotational orientation, the crankshaft configured to be disposed in a generally vertical orientation during operation;
• a combustion chamber fluidly coupled with the first cylinder and the second cylinder to continuously define a fluid volume including the combustion chamber, the first cylinder, and the second cylinder;
• an ignition source at least partially disposed within the combustion chamber;
• an intake valve providing selective fluid communication between an intake system and the combustion chamber;
• and
• an exhaust valve providing selective fluid communication between an exhaust system and the combustion chamber.