Restore proper compression and support reliable engine performance with Namura NA-40012R piston rings. Designed specifically for use with Namura pistons, this ring set provides a precision replacement solution for compatible Yamaha engines requiring a 4.01-inch piston ring size. The rings are intended for engine rebuilding, top-end service, and replacement of worn or damaged components.
These Namura piston rings are manufactured for accurate fitment with the corresponding Namura piston application. Proper ring selection is essential for maintaining cylinder sealing, controlling oil consumption, and supporting efficient combustion. Before installation, verify the piston, cylinder, bore condition, and engine application to ensure compatibility. These rings are for Namura pistons only and may not be suitable for pistons from other manufacturers.
Install the Namura NA-40012R rings according to the applicable Yamaha engine service procedures, including correct ring orientation, end-gap inspection, and cylinder preparation. The manufacturer part number is NA-40012R, and the vendor part number is 186-4012R. Use this replacement ring set when servicing a compatible Yamaha engine equipped with Namura pistons and a 4.01-inch piston specification.
Features:
- Size: 4.01-inch piston ring size
- Application: Replacement piston rings for compatible Yamaha engines
- Brand: Namura
- Model: NA-40012R
- Manufacturer Part Number: NA-40012R
- Vendor Part Number: 186-4012R
- Fitment: Designed for Namura pistons only
- Service Use: Suitable for top-end repairs, engine rebuilding, and worn ring replacement