Rocker Arm Assembly Compatible with FS-120S, S-II, S-E, S-SP, FT-300 - O.S. Engine OS45561010  [OS45561010]

O.S. ENGINES ROCKER ARM ASSEMBLY FS-120S,S-II,S-E,S-SP,FT-300
Price:
AUD$22.62
Brand:
O.S. Engine
Model:
OS45561010
GTIN:
4531028123519
Condition:
Brand New
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Valve actuation rocker for FS engines

This rocker arm assembly is an RC-scale replacement part specified by the manufacturer for the listed FS-series engines. It provides the linkage that transmits cam motion to the valves and restores correct geometry when worn components alter timing.

Compatibility is restricted to the model numbers displayed in the product title; confirm OS45561010 against your engine model before purchase. While servicing, keep an eye on clearance tolerances and secure all fastenings to ensure consistent engine behaviour under model operating conditions.

Because the rocker arm influences valve timing and responsiveness, include rocker alignment and rocker-to-valve clearance checks in any tuning or replacement routine to preserve expected engine performance for RC use.

Specifications

  • Item: Rocker Arm Assembly
  • Material: Not specified by manufacturer
  • Model Number: OS45561010
  • Compatibility: FS-120S, S-II, S-E, S-SP, FT-300

Use this original replacement component to rebuild valve linkage on compatible FS-series engines and follow standard reassembly inspections for clearance and mounting security.

How does a new rocker arm affect valve timing?

A correctly installed rocker arm restores intended geometry, which can change valve timing slightly compared with a worn component. After replacement reconfirm settings and run a tuning check to fine-tune performance.

Should I re-check carb and ignition after replacing the rocker?

Yes. Because valve timing and response can shift, verify carburation and ignition settings during a post-installation run-in to ensure the engine idles and revs smoothly.

Is additional machining or fitting normally required?

No. This part is intended to fit the listed FS models without extra machining. If fitment problems occur, stop and consult an authorised dealer rather than forcing the component.

What routine checks keep the rocker assembly reliable?

Regularly inspect for wear, verify valve lash, and ensure fasteners remain tight. Replace the assembly if you observe play or deformation that could affect timing.

Can I reuse the original fasteners when fitting this part?

If original fasteners show no wear or thread damage they can typically be reused, but replace any that are stretched, corroded or damaged and always torque to the engine manual specification.

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