Some don't tap into the ignition at all. Some are purely mechanical, equipped with a little rubber tip that you press against the end of the crankshaft to directly read RPM. Others have an optical sensor, and come with a little strip of reflective tape that you stick on the side of a flywheel or vibe damper. read more
But a 2 stroke engine fires once every revolution, piston moving down is one stroke once it starts moving back up it is considered a different stroke and therefore number 2. Most 4stroke small engines, like Briggs and Stratton's or Tecumseh's fire every revolution also, but the universal tachometers have a setting for those that makes them ignore every other spark signal to differentiate them from a 2 stroke. read more
Difference Between 2 Stroke and 4 Stroke Engines June 3, 2014 February 22, 2018 Pankaj Mishra 8 Comments Automobile, Difference between In this post I am going to tell you about the difference between two stroke and four stroke engines. read more