The word tachometer is derived from two Greek words: tachos, meaning speed, and metron, meaning measure. In this instance, a tachometer is used to measure the rotation speed of a disk or a shaft located within a small engine. Tachometers can be used by motorists to gauge their vehicle’s revolutions per minute (RPM). This information is invaluable to motorists because it helps them to maintain a safe speed while driving. This will help them avoid overheating, inadequate lubrication, and damage to sub-parts of the engine. These issues can eventually lead to the partial or total breakdown of the engine. A tachometer also serves the same purpose for mechanics. The readings from a tachometer can provide them with their next course of action, saving time and money for the consumer. Here are the most recommended small engine tachometers.