Yamaha 7A9-11610-21-00 - Ring Piston Set (2ND O-S) is a genuine Yamaha part. It replaces a worn or damaged engine component with the specified Yamaha part. Use part number 7A9-11610-21-00 to confirm it matches the component shown in your model's Yamaha parts diagram.

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Key Features & Benefits

• Installs in the position shown in the Yamaha engine parts diagram.
• Built to Yamaha's specification for its engine location.
• Replaces worn, scored, or damaged engine components.
• Size designation 2ND O-S as listed by Yamaha; confirm the required size with service manual measurements.
• Sold under Yamaha part number 7A9-11610-21-00.

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Frequently Asked Questions

Is 7A9-11610-21-00 a genuine Yamaha part?

Yes. 7A9-11610-21-00 is the Yamaha part number for the Ring Piston Set (2ND O-S). It is an internal engine component built to Yamaha's specification.

What does the 2ND O-S size on part 7A9-11610-21-00 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists 7A9-11610-21-00 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.

How do I confirm 7A9-11610-21-00 fits my Yamaha?

Model fitment is not listed for part 7A9-11610-21-00 on this page. Compare the part number against the Yamaha parts diagram for your model and year, or confirm with a Yamaha dealer using your model or VIN 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.