Carburetor Jet Drill Bits & Drill Bit Sets

Carbide micro drill sets for carburetor jet sizing, cleaning, matching, and careful tuning. Options cover small-engine, motorcycle, automotive, and common Holley, Rochester, Carter, Mikuni, Weber, Keihin, and Walbro applications.


Need a specific individual drill size? Browse individual carbide drill bits.


Choosing a Carburetor Jet Drill Set

Compare drill size ranges and applications to find the right carburetor jet drill set for your project.

Small Carburetor Jets

20 Pc Selected Sizes Carburetor Jet Drill Set

Versatile starter set for small carburetor jets, including Mikuni, Keihin, Weber, Walbro-style applications, motorcycles, scooters, ATVs, and small engines.

View the 20 Pc Set →
Keihin | Pilot & Slow Jets

K10 – 10 Pc Keihin Pilot & Slow Jet Drill Set

0.35–0.80 mm. For smaller pilot and slow jets in Keihin carburetors.

View the K10 Set →
Keihin | Main Jets

K20 – 20 Pc Keihin Main Jet Drill Set

0.85–1.80 mm. For larger main jet applications in Keihin carburetors.

View the K20 Set →
Keihin | Complete Range

K30 – 30 Pc Keihin Pilot, Slow & Main Jet Drill Set

0.35–1.80 mm. Combines the K10 and K20 ranges for pilot, slow, and main jet applications.

View the K30 Set →
Continuous Numbered Sizes

25 Pc #75–#51 Carburetor Jet Drill Set

Continuous numbered-drill coverage for checking, cleaning, matching, and carefully tuning carburetor jets.

View the 25 Pc Set →
Two Drills Per Size

D7 50 Pc #80–#56 Carburetor Jet Drill Set

50 carbide drills covering 25 numbered sizes, with two drills of each size.

View the D7 Set →
Larger Automotive Jets

HS1 .040"–.125" Holley Carburetor Jet Drill Set

For larger automotive jet applications, including Holley, Rochester, Carter, Quadrajet-style, and AFB/AVS-style carburetors.

View the HS1 Set →
Ford Model A | Zenith

Ford Model A Zenith Carburetor Jet Drill Kit

A dedicated drill kit for Ford Model A Zenith carburetor jet sizes.

View the Zenith Set →

Tip: Choose the smallest set covering your required jet sizes. Enlarge jets gradually—removed material cannot be replaced. Drill diameter alone does not guarantee an exact fuel-flow rate.

About Carburetor Jet Drills

Carbide micro drills are well suited for careful work on small brass carburetor jets and other soft-metal metering parts. Because carbide is hard and rigid but also brittle, use a stable, accurately aligned setup with minimal runout. A precision drill press or micro-drill fixture is preferable, especially for the smallest diameters.

When enlarging a jet, use light pressure, keep the drill square to the opening, and increase the size gradually. Avoid side-loading, bending, hand wobble, or forcing the drill—especially with the smallest diameters.

These drills use a common 1/8" shank and are approximately 1.50" overall length. Very small drills require especially light feed pressure and minimal runout.

Important: Drilling a jet changes its physical opening, but drill diameter alone does not guarantee an exact fuel-flow rate. For precise fuel-flow work, final sizing may require jet reaming or flow testing.

Carburetor Jet Drill Resources

Need help matching carburetor jet numbers to drill sizes?

Use these reference guides to compare carburetor jet numbers, approximate opening sizes, practical drill size ranges, and recommended drill sets:

Need a specific drill diameter?

Browse individual carbide drill sizes for matching, cleaning, or carefully enlarging a specific jet.

Looking for other drill set options?

Browse carbide drill sets, including incremental, metric, fractional, and larger multi-size assortments.