The Yamaha YZ 125 has been a popular model for many years, as anyone can pick one up and have a blast riding it. A solid platform straight off the showroom floor, we decided to have Bill’s Pipes go through the engine of the small-bore two-stroke in order to see what it’s truly capable of. Jeff Springman ported and polished the cylinder, dropped in a high compression Wiseco single-ring race piston, over bored the carburetor, installed the new Moto Tassinari VForce4R reed block, and bolted on the Bill’s Pipes MX2 expansion chamber and MX2 carbon fiber silencer combo.
Interested in having Bill’s Pipes go through your motor? Contact the California hop-up shop for complete details on their in-house engine services.
Bill’s Pipes Port & Polish Race Spec Engine Package | $350
Carburetor Modification | $80
Bill’s Pipes MX2 Expansion Chamber | $239.99
Bill’s Pipes MX2 Carbon Fiber Silencer | $229.99
MotoTassinari VForce4R Reed Block | $168
Wiseco Single-Ring Race Piston | $142