YGQ Carburetor Jet Kit for Mikuni VM/TM/HSR Carburetors — 42‑Piece Jet Assortment, Main & Pilot Jets

YGQ's 42-piece carburetor jet kit supplies a wide range of precision main and pilot jets designed to tune Mikuni VM, TM, HSR and related carburetors for improved throttle response and fuel metering.

This kit gathers commonly needed metering jets and pilot slow jets in one organized assortment so mechanics, tuners and DIY riders can quickly match jetting to altitude, fuel quality, or engine mods. It covers multiple Mikuni families — VM round and smoothbore, TM flat-slide, HSR and HS series — and fits many popular motorcycle, ATV and off‑road platforms from Honda, Yamaha, Suzuki, Kawasaki and Polaris. The set includes both large round and hex main jets plus two pilot jet series so you can refine both high- and low-speed fueling.

Which jet sizes are included and why they matter?

The kit contains a broad spread of main jet diameters and two pilot slow jet ranges so you can adjust for lean or rich conditions across the RPM band. Main jets control high‑fuel flow (top-end performance), while pilot jets tune idle and low‑throttle response.

• Large round main jets: 90, 100, 110, 120, 125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 190.
• Large hex main jets: 130, 140, 150, 160, 170, 180, 200, 220, 240, 260, 280.
• TM pilot slow sizes: 17.5, 20, 25, 30, 35, 40.
• VM pilot slow sizes: 25, 30, 35, 40, 45, 50, 55, 60.

Which carburetors and needle jets is this kit compatible with?

This assortment is built to fit many Mikuni models — both round and flat slide designs — and it matches several needle jet series used across those carbs. That makes it convenient when swapping jets across different applications or when upgrading components.

• Compatible carbs: VM16–VM44 series, VM18, VM20, VM22, VM24, VM26, VM28, VM30, VM32, VM34, VM36, VM38, VM44.
• Also fits many TM24–TMX family carbs, HS/HSR/HSR42/HSR45, RS34–RS40 and select flat slide models.
• Compatible needle jet series include 171, 188, 196 (with large round), and 568, 640, 723.

Will this kit work on my motorcycle, ATV or off‑road machine?

If your vehicle uses Mikuni VM/TM/HSR-style carburetors or equivalent replacement units, this kit will cover most common tuning needs for 2‑stroke and 4‑stroke engines. It’s intended for riders who need flexible jetting options without sourcing individual jets separately.

• Common installs: Honda, Yamaha, Suzuki, Kawasaki and Polaris models with compatible Mikuni carbs.
• Applications: street bikes, dirt bikes, ATVs, UTVs and other off‑road machines requiring precise jet selection.
• Useful for: altitude changes, fuel grade variations, performance upgrades, and troubleshooting poor pilot/high‑end mixture.

How should I use the kit to optimize jetting safely?

Start with the factory-recommended jet or a known baseline, then change one jet at a time and test under controlled conditions. Keep a log of jet sizes and results; small incremental steps prevent over‑fueling or running too lean.

• Begin at idle and part throttle to dial pilot jets, then move to main jet trials for full-throttle tuning.
• Record conditions (altitude, temperature, fuel) to reproduce successful settings later.
• Use a clean workspace and magnetic tray to avoid losing tiny jets during swaps.

Who is this for? The YGQ 42-piece Mikuni jet kit is built for mechanics, race teams, hobby tuners and weekend riders who need a comprehensive, cost-effective selection of main and pilot jets. If you own or service bikes and ATVs with Mikuni VM/TM/HSR carburetors or similar units, this set simplifies finding the correct jetting for performance tuning, fuel‑quality adjustments, and seasonal or altitude changes.