Yamaha 7A9-11635-02-00 - Piston (1ST O-S) 73.25MM is a genuine Yamaha part. It is an internal engine component built to Yamaha's specification. Ordering by part number 7A9-11635-02-00 ensures you receive the exact component Yamaha lists for its location.

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Key Features & Benefits

• Built to Yamaha's specification for its engine location.
• Replaces worn, scored, or damaged engine components.
• Installs in the position shown in the Yamaha engine parts diagram.
• Size designation 1ST O-S as listed by Yamaha; confirm the required size with service manual measurements.

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Frequently Asked Questions

What is Yamaha part 7A9-11635-02-00?

7A9-11635-02-00 is the Yamaha part number for the Piston (1ST O-S) 73.25MM, a genuine Yamaha part. This engine part is one of the internal components that keep the engine running as designed.

What does the 1ST O-S size on part 7A9-11635-02-00 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists 7A9-11635-02-00 as 1ST O-S, which is used when the mating part has been machined or worn to match. Measure and confirm the required size using the Yamaha service manual.

Should related parts be replaced with the Piston (1ST O-S) 73.25MM (7A9-11635-02-00)?

When replacing engine internals, inspect mating parts and replace gaskets and seals disturbed during disassembly. Refer to the Yamaha service manual for your model when installing 7A9-11635-02-00.

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WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.