What components are involved in the flywheel installation?

The correct choice is comprehensive because it lists all necessary components that play a critical role in the flywheel installation process. The flywheel itself is essential as it helps smooth out the power delivery from the engine and store energy to keep the engine running smoothly. The flywheel key is crucial for ensuring that the flywheel is properly aligned and securely fastened to the crankshaft; it prevents any slipping that might disrupt engine timing and performance.

Additionally, the presence of the flywheel shield is important for safety. This component protects the user from any debris ejected from the flywheel during operation. Lastly, while the valves are not directly involved in the installation, their inclusion can signal understanding of the engine's broader systems. The overall assembly must also consider clearances and other factors that may involve the valves when the flywheel is installed.

In summary, selecting the comprehensive answer reflects a complete understanding of the context surrounding flywheel installation in small engines, ensuring both functionality and safety.