HJ340-4 Mikuni hex head main jets 4/042, size 340

When it comes to fueling, there is no room for guesswork. These EBC Mikuni hex head main jets are manufactured by A-BAX Precision Engineering to provide the accuracy needed for high-performance tuning. This size 340 jet follows the 4/042 design and is a direct fit for Mikuni VM series, VM-18, VM24-512, VM26-606, and TMX carburetors. A properly sized main jet is critical for maintaining the correct air-fuel ratio at wide-open throttle, preventing lean conditions that can lead to engine damage. These precision-machined brass jets are sold as a pack of four, making them an essential addition to any Harley mechanic's carburetor service kit when working on Mikuni-equipped machines.