Motorcycle Engine Parts Piston Rings Kit Bore STD Size 66mm For TR250 250 Piston rings kit designed for single cylinder motorcycle engines with a standard bore size of 66mm.Constructed from nodular cast iron, the set provides performance and resistance to wear under operating temperatures.The material composition supports stable engine and helps maintain compression efficiency.This piston ring kit meets ISO9001 standards for consistent manufacturing quality.Suitable for use in compatible engine models requiring a 66mm bore fitment.The design allows for straightforward installation as part of routine engine maintenance or rebuilds.Includes all necessary components for replacement applications.