Radial Engine

The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes of a wheel.

It resembles a stylized star when viewed from the front, and is called a "star engine" (German Sternmotor, French Moteur en étoile) in some languages. 
The radial configuration was very commonly used in aircraft engines before turbine engines became predominant.

Inside the Radial Engine:
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel. This configuration was very commonly used in large aircraft engines before most large aircraft started using turbine engines. In a radial engine, the pistons are connected to the crankshaft with a master-and-articulating-rod assembly.
Radial Engine Powered Motorcycle