Mikuni J8-6EJ12-54 Jet Needle for Flat Slide Carburetor Jets - TMX38

The Mikuni J8-6EJ12-54 is a genuine OEM jet needle designed specifically for TMX38 flat slide carburetors. This precision-engineered component controls fuel metering during mid-range throttle operation, directly affecting engine performance between 1/4 and 3/4 throttle positions.

Key Specifications:

• Part Number: J8-6EJ12-54 (also referenced as 6EJ12-54)
• Needle Length: 66.7mm overall
• Length to Taper: 25.5mm
• Application: Mikuni TMX38 flat slide carburetors
• Original Mikuni OEM quality with stamped part number

Function and Performance:

• Tapered design meters fuel flow as throttle valve opens
• Works with fixed needle jet to maintain proper air/fuel ratio
• Position adjustable via E-clip for fine-tuning carburetor performance
• Controls fuel mixture in critical mid-range throttle range

The 6EJ12 series needles are commonly used in TMX38 applications for high-performance two-stroke engines, including motorcycles, snowmobiles, and other powersports vehicles. The -54 designation indicates this needle is on the leaner side of the 6EJ12 range, which extends from -54 through -60, allowing precise tuning for different engine configurations and altitude conditions.

This genuine Mikuni component ensures reliable performance and proper fuel metering when installed in compatible TMX flat slide carburetors. The jet needle works in conjunction with the throttle slide and needle jet to provide smooth throttle response and optimal engine performance throughout the mid-range power band.