O.S. Engine OS29708200 PARAREL KEY GT55 engine accessory  [OS29708200]

Parallel key for GT55 engines

This O.S. Engine parallel key is an RC-scale engine accessory intended to seat in a shaft keyway and transmit torque between crankshaft and mounted components such as flywheels or clutch interfaces. It serves a clear tuning and maintenance role by keeping rotational parts indexed and preventing slippage under load.

Installation is straightforward: align the keyway on the shaft and the mating hub, slide the key into the shaft slot until it sits flush or slightly proud depending on the hub fit, then assemble the hub or flywheel and check for tight, wobble-free rotation. Inspect the key periodically for wear during tuning sessions or after high-rev testing, and replace if any deformation appears.

For setup and tuning, use the key as a mechanical datum to ensure repeatable timing and orientation of external components. Avoid forcing the part into an undersized slot; a light tap or gentle pressing to seat the key is sufficient for most RC engine assemblies. This item is presented as a simple replacement or spares part for RC-scale engine work.