Yamaha 7A9-11636-02-00 - Piston (2ND O-S) 73.50MM is a genuine Yamaha part. It is an internal engine component built to Yamaha's specification. Confirm part number 7A9-11636-02-00 against your Yamaha parts diagram before ordering.

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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 2ND O-S as listed by Yamaha; confirm the required size with service manual measurements.

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Frequently Asked Questions

What is the Yamaha Piston (2ND O-S) 73.50MM (7A9-11636-02-00)?

The Piston (2ND O-S) 73.50MM is a genuine Yamaha part sold under part number 7A9-11636-02-00. This engine part is one of the internal components that keep the engine running as designed.

What does the 2ND O-S size on part 7A9-11636-02-00 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists 7A9-11636-02-00 as 2ND 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.

Which Yamaha models use the Piston (2ND O-S) 73.50MM (7A9-11636-02-00)?

Model and year fitment data is not listed for 7A9-11636-02-00 on this page. Look up your model's Yamaha parts diagram and confirm that it lists part 7A9-11636-02-00 before ordering.

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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.