Thunder Bike Piston Rings Bore 3.880 inch (98,552 mm ) Compression rings: 4 - 1.5MM, oil segment: 2 - 2.5MM +.005 mm Moly 1690 ccm (103 cui)

Thunder Bike Piston Ring sets are manufactured by Hastings and are the perfect blend of materials and design that complement one another to provide long-lasting oil and blow-by control as well as maximum power.

Features:

• All ring faces are pre-lapped for easier seating
• In the moly sets, the compression ring features a moly insert on its barrel face design.
• The exclusive Flex-Vent oil control ring is easy to install because it fits from both up-down side. It can’t overlap, can’t gouge and can’t be installed wrong.
• With its open design, it provides 200% greater drainage capacity than conventional designs.

Specifications:

• Diameter: 98.4 mm
• Oversize: +.005 mm
• Material: Moly

Compatibility: 1550 cc and 1690 cc engines