Beside this, what should the gap be on a spark plug for a lawn mower?
Accordingly, do Honda lawn mower spark plugs come pre gapped? Champion spark plugs traditionally leave the factory pre-gapped for their most popular application. However, a plug may fit hundreds of engines, from cars to golf carts. Gapping the plugs to your engine's specifications is important to prevent pre-ignition, detonation, fouling and poor fuel economy.
Here's how a standard OEM Honda plug is constructed: Platinum or Iridium Center Electrode. A OEM Honda plug will have a platinum (90k mile rating) or iridium tip (120k mile rating). These are both costly metals, but prolong the life of your plug.
Spark plugs that are gapped incorrectly can cause an engine to miss, or run erratically, especially during idle. The incorrect spark plug gaps can cause uneven firing of individual spark plugs and delay engine combustion; both of which can cause an engine to miss or idle erratically.
If the gap is too small, the spark will likely be too weak and cause the engine to run poorly or with poor efficiency. ... A spark-plug gap gauge both measures and adjusts the gap and is inexpensive and simple to use.