Drill Sets for Carburetor Jet Tuning

A convenient selection of pre-configured micro drill sets for carburetor jet tuning, small engine work, automotive carburetors, motorcycles, scooters, go-karts, radio-controlled engine carburetors, and similar precision fuel-metering applications.

Each set includes a range of small drill sizes commonly used when checking, matching, or carefully enlarging carburetor jet openings. These sets are especially useful when replacement jets are difficult to find, when working with older carburetors, or when tuning in small size increments.

Comes in a sturdy plastic case to help keep your drills protected, organized, and easy to identify. A handy size index is included.

Carburetor Jet Drill Set Basics

These precision micro drills are intended for careful work on small brass carburetor jets and similar soft-metal metering parts. They are useful for controlled jet-size changes, but jet modification should be done gradually and carefully because once a jet is enlarged, it cannot be returned to its original size.

  • Useful for Carburetor Jet Tuning
    Ideal for working with main jets, pilot jets, air bleeds, and other small carburetor metering passages where small changes in opening size can affect fuel or air flow.
  • Small Increment Size Selection
    Pre-configured sets provide a practical range of micro sizes for stepping up gradually instead of jumping too far in one cut.
  • Solid Carbide Precision Drills
    Carbide drills are hard, rigid, and capable of producing clean, accurate holes when properly supported. They are best used in a drill press, pin vise, micro drill fixture, or other controlled setup rather than with side pressure or hand wobble.
  • 1/8" Shank (3.175 mm)
    The common 1/8" shank fits many small drill chucks, collets, rotary tool accessories, and precision drilling setups.
  • Short 1.50" Overall Length
    The short overall length helps reduce flex and improve control when working with very small drill diameters.
  • Size Index Included
    Helps identify the included drill sizes quickly when comparing drill diameter, jet size, or tuning steps.

Important Use Notes

  • Best suited for brass carburetor jets and other small soft-metal metering parts.
  • Use light pressure, keep the jet square to the drill, and increase size gradually.
  • Do not skip multiple sizes when tuning; it is easy to remove too much material.
  • Carbide micro drills are hard but brittle. Avoid bending, side-loading, or forcing the drill.
  • For the most precise fuel-flow work, final sizing may require reaming or flow testing, since carburetor jet flow can depend on more than the drilled hole diameter alone.

Looking for individual drill sizes?
View Individual Drills →

Need a specific replacement size?
The shank size stays the same — only the cutting diameter changes. Choose individual drill sizes when you need a specific diameter for matching, checking, or carefully enlarging a particular jet.