Athena P400485100029 144cc Big Bore Cylinder Kit with Cylinder Head (58mm Bore) - Premium 2-Stroke Performance Upgrade, Compatible with Yamaha YZ125 1997-2004 DOMANKI 250 rpm to drive large-diameter

250 rpm to drive large-diameter screws

Designed as an exact OEM-style replacement

improves throttle response

25-12 TR87 Motorcycle Inner Tube

Athena P400485100029 144cc Big Bore Cylinder Kit with Cylinder Head (58mm Bore) - Premium 2-Stroke Performance Upgrade, Compatible with Yamaha YZ125 1997-2004 DOMANKI 250 rpm to drive large-diameterUPGRADE YOUR DIRT BIKE TO THE NEXT LEVEL OF PERFORMANCE Extract massive power, aggressive low end torque, and unmatched acceleration from your 125cc two stroke racing engine with the Athena Big Bore Cylinder Kit (Part No. P400485100029), a premium race proven package engineered in Italy to seamlessly convert your factory setup into a high revving, high output 144cc powerhouse. Entirely cast from high grade aluminum and treated with a specialized Motor