NGK GR9DI-8 Spark Plug for Rotax Max Evo Kart Engines. This spark plug is one of (2) legal spark plugs for Rotax USMRC competitions and operation.
The NGK GR9DI-8 is designed to run in slightly cooler temperatures or denser air, and is considered a 'hotter' plug (burns hotter) than the GR8-DI.
Note: Always check with your local Rotax regulations and competition rule set prior to running any spark plug with your Rotax! These are a tech item, so be sure to make sure you are allowed to run this in your specific category.