What does a dial indicator specifically measure?

A dial indicator is a precision measuring instrument primarily used to measure small distances and movements with a high degree of accuracy. Specifically, it measures linear movement or displacement of components, allowing users to assess gaps, runout, or other minute movements in fractions of an inch or millimeters. This capability makes it invaluable in various mechanical applications, including aligning engine components, checking tolerances, and ensuring proper fitment.

In contrast, measuring torque involves ingredients such as a torque wrench, which is designed specifically for that purpose, whereas capturing engine RPM is the function of a tachometer. The gap size of spark plugs can be assessed with feeler gauges rather than a dial indicator. Thus, the focus of the dial indicator on detecting small movements and gaps makes it an essential tool in small engine technology.