Namura Top End Rebuild Kit for Yamaha YFB250 YFM250 Models 72.45mm NA 40015 6K 2003 Yamaha YFM400 Big Bear Product Details Product Line Cycle Product Details Product Line Cycle Works Replacement Seat Cover Part Number 36 26500 01 Fitment Type Model Specific Fitment Use Type Unit Sale Qty Each Style Position Material UV resistant Marine Grade Vinyl Color Black Finish Gripper Black Driver Seat Length Passenger Seat Length Driver Seat Width Passenger Seat Width Overall Seat Width Overall Seat Length Product Disclaimer Fitment Note Fitment Note Fitment Note Fitment Note Fitment Note Product Details Tire Diameter Speed Rating Load Rating Wall Construction Tire Tube Type Rim Size Product Line Electrosport Plug In Regulator Rectifier Part Number ESR341 Fitment Type Unit Sale Qty Style Material Color Size Finish Position Functional Length Cable Sleeve Length Cable Sleeve Travel Driver Seat Length Passenger Seat Length Driver Seat Width Passenger Seat Width Piston Cylinder Size Piston Size Added Cylinder Stroke Volume Final Engine Displacement Exhaust Configuration Muffler Size Muffler End Tip Style Windshield Height Windshield Width Handlebar Diameter Ca ARB Compliance Non CARB Complaint CARB Compliant Product Disclaimer 45mm Age Group Gender Position Tire Diameter Speed Rating Load Rating Wall Construction Tire Tube Type Rim Size Material Color Finish Functional Length Cable Sleeve Length Cable Sleeve Travel Driver Seat Length Passenger Seat Length Driver Seat Width Passenger Seat Width Overall Seat Width Overall Seat Length Piston Cylinder Size 72 Namura gives you a higher performance piston without the higher price