Yamaha YZF R1 Crossplane Crankshaft Technology Explained!

Crossplane CrankshaftCrossplane Crankshaft

Yamaha’s R1 has a crossplane crankshaft. The crossplane crankshaft is designed to reduce inertia torque created by the engine to a minimum. A conventional four-cylinder engine (flat-plane crank) has it’s crankpins all in the same plane, with the two inner ones 180 degrees from the two outer ones. The inner two pistons move up and down together, and so do the two outer ones, and it’s this particular configuration which generates something called inertial torque.

Yamaha YZF R1 Crossplane Crankshaft Technology Explained!

On Yamaha’s cross-plane crankshaft, these fluctuations are all but eliminated. In this layout the crankpins are distributed at 90 degrees to each other around the crankshaft. So as one piston is slowing down and losing energy to the crank, another is speeding up and taking the same amount back. At no point do all the pistons stop together, as they do on a flat-plane crank. Instead the energy flow is evened out and the rotation of the crank is almost completely smooth and steady.

Check it out!