| Glossary P | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0..9 | A | B | C | D | E | F | G | H | I | J | K | L | M |
| Misc | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Parallel Twin A two-cylinder engine layout in which both cylinders are side by side and mounted across the frame.
Pinion A small gear.
Planetary Gear A gear driven by a central sun gear or crownwheel.
Plunger Suspension A suspension system in which the vertical movement of the axle is controlled by springs mounted above and below the axle.
Port Opening into a cylinder.
Port Timing In two-stroke engines the critical moment when ports are covered or uncovered by the piston.
Pressed Steel Sheet steel made into curved sections by press forming. It is often used in the construction of the frame and forks.
Pre-Unit An engine and gearbox that are not built together in the same casing Ore-unit construction was common on earlier motorcycles.
Primary Drive The system of transferring power from the engine to the gearbox. Usually achieved by chain or gear.
Pivateers Racers who do not have the backing of a manufacturer.
Pushrod Metal rod used to transmit linear motion, most often from camshaft to rocker arm on o.h.v. engines.