P

Also known as a slow fuel jet, it controls the fuel delivered to the pilot circuit of a carburetor. Can be accessed by removing the float bowl. … [Read more...] about Pilot Jet

The moving part of a typical motorcycle clutch assembly that, working against clutch spring tension, releases the clamping action on the clutch plates when the clutch lever is engaged. … [Read more...] about Pressure Plate

An emergency stop, requiring hard, effective controlled brake application, so called because it is often conducted during a moment of panic. … [Read more...] about Panic-brake

The part of a piston that is below the bottom piston ring and piston pin boss. The skirt acts as a guide as the piston goes up and down in the cylinder. It is often the part that shatters when the piston-to-cylinder clearance becomes excessive allowing the piston to rock in the bore. … [Read more...] about Piston Skirt

A diagnostic test used to check the electrical system of a motorcycle for current flow (amperage) when the key is off. The purpose of this test is to ascertain whether the battery is being drained while the vehicle is not in use. Some devices with memories such as clocks, radios and digital … [Read more...] about Parasitic Draw Test

A screw mounted on the side or bottom of a motorcycle carburetor that allows adjustment of the air/fuel ratio in the pilot circuit of a slide type carburetor. Also known as the idle air screw or the low speed air screw. … [Read more...] about Pilot Air Screw

A very common way of wiring the different circuits on a motorcycle where current is provided to each electrical circuit independently of the others. The failure of one circuit does not affect the rest of the circuits. … [Read more...] about Parallel Circuit

In terms of motorcycle and ATV suspensions, spring preload is the static length of a spring (as it is installed in a motorcycle fork or shock) subtracted from its free length (as it is uninstalled). The spring preload determines the motorcycle ride height and sag. In motorcycle forks, preload is … [Read more...] about Preload