C70 Piston Ring 47mm

C70 Piston Ring

For Moped, Cub & ATV

Fits Engines: 139FMB 147FMD 147FMF 150FMG

High-quality C70 piston rings for 70-90cc horizontal engines, providing reliable cylinder sealing and oil control.

This product is a C70 series piston ring set, designed for 70-90cc horizontal engines used in mopeds, Cub motorcycles, and ATVs. It perfectly fits classic engine models such as 139FMB, 147FMD, 147FMF, and 150FMG. The piston rings are made of high-quality alloy cast iron, offering excellent wear resistance, elasticity, and high-temperature stability. They effectively seal the combustion chamber, control oil consumption, and conduct heat, ensuring strong power output and smooth engine operation.

These piston rings are primarily compatible with the following 70-90cc horizontal engines (widely used in mopeds, Cubs, ATVs, etc.):

• Quality Material: Made of alloy cast iron, offering excellent wear resistance, heat tolerance, and tensile strength for long service life.
• Precision Forming: End gap, side clearance, and back clearance are precisely controlled to ensure perfect fit against the cylinder wall after installation.
• Excellent Sealing: Compression rings provide effective sealing for strong cylinder pressure; oil control ring efficiently scrapes oil to reduce consumption and carbon buildup.
• Direct Replacement: Designed to original specifications, these rings directly replace worn original parts without any modifications.

✅ Typical Symptoms of Worn or Damaged Piston Rings: Hard starting, significant power loss, burning oil (blue smoke from exhaust), excessive oil consumption, low compression, heavy spark plug fouling. If you experience these issues, the piston rings may need inspection or replacement.

⚠️ Installation Note: When installing piston rings, pay attention to the ring orientation and stagger the ring end gaps (typically 120 or 180 degrees apart) to prevent blow-by. Use a proper piston ring expander tool to avoid deforming or breaking the rings. New piston rings are best used with a new or honed cylinder for optimal sealing. Allow proper engine break-in after installation.