RPM (revs)

RPM stands for revolutions per minute and shows how fast the crankshaft is turning. Riders often just say revs. Engine speed is displayed on the tachometer, usually in thousands, so a needle on 6 means 6000 rpm.

Power is the product of torque and rpm, so an engine makes its peak power at fairly high revs, while peak torque usually comes lower in the range. Small high-revving engines need more revs to pull, whereas big twins pull strongly from low rpm.

Practical tips: avoid labouring the engine at very low rpm in a high gear, do not rev a cold engine hard, and respect the redline. Idle speed is also given in rpm in the service manual.