EJK modules are interesting for riders who want to easily adjust the fuel tuning after modifications to the exhaust or air intake. The modules work as piggyback EFI controllers and are usually set via buttons on the module, without a separate computer or extensive software mapping.
Always pay close attention to the exact engine model, year, injection system, and modifications on the engine when dealing with EJK. A fuel module is a technical part of the engine tuning and must be chosen appropriately and set correctly. Current availability may vary by product and version.