Engine Braking

When you shut the throttle with the clutch engaged, the rear wheel has to keep turning the engine against its compression and internal friction, so the bike slows down. This is engine braking. It is strongest in low gears, on large single- and twin-cylinder four-strokes, and weakest on two-strokes.

Engine braking is useful on long descents and for smooth riding, but it does not turn on the brake light, so following traffic gets less warning. Sudden heavy engine braking on a slippery surface can lock or hop the rear wheel; slipper clutches and electronic engine-brake control limit this.

Off-road, engine braking in a low gear is a key technique for steep downhills. On automatic scooters it is much weaker because of the CVT.