YAMAKATO 27mm Carburetor for Predator GX340 GX390 Compatible 338–459cc Engines — Jet Kit, Gaskets Included

YAMAKATO's 27mm OEM-standard carburetor kit replaces and upgrades carburetion on 338cc–459cc small engines like Predator, GX340/GX390 and compatible clones.

This carburetor assembly is a bolt-in style replacement designed for mini bikes, go-karts, pressure washers, snow blowers and other small-engine machines where improved fuel metering and wider jetting options are required. The kit centers on a 27mm carb body built to OEM dimensions and comes with a selection of main jets, fuel line and mounting gaskets so you can tune fuel delivery for altitude, load and performance needs. It is intended for recreational and utility engines—double-check compatibility with generator-specific engines before ordering.

Will this carburetor fit my Predator, Honda clone or GX-series engine?

Compatibility covers a range of 338cc–459cc single-cylinder engines and many common clones. It is made to fit engines using a 27mm carburetor flange and throttle linkage layout similar to Honda GX and Predator series.

• Fits many 420cc, 389cc, 459cc, 338cc, 337cc and 390cc small engines.
• Works with brands like Predator, GX340/GX390 clones, Lifan, Ducar, Loncin and similar.
• Not guaranteed for all generator models—confirm flange and intake spacing before purchase.

How do the included jets and components help me tune performance?

The kit includes seven main jets spanning lean to rich sizes so you can dial in the air–fuel ratio for your specific conditions. Swapping jets lets you adapt for altitude, throttle response and load without having to buy separate jets later.

• Main jets included: 040–046 (approximate sizing) to cover a broad tuning range.
• Fuel line and mounting gaskets included for a complete install without extra hardware.
• Test jets one at a time and monitor plug color and throttle response to find the right jet.

What installation and tuning steps should I expect?

Installation follows standard carburetor replacement steps and requires basic hand tools. After mounting the carb, start with a mid-range jet from the kit, warm the engine, then adjust up or down based on performance and spark plug inspection.

• Remove old carburetor, transfer throttle/choke linkages and install supplied gaskets.
• Start with a medium jet and run the engine at various throttle positions to evaluate.
• Fine-tune using richer or leaner jets supplied until desired response is achieved.

What should I avoid and how do I maintain this carburetor?

Avoid using this kit on engines with incompatible flange patterns or specialized generator carb setups. Regular cleaning and occasional jet inspection keep the carburetor operating reliably in dirty or fuel-contaminated environments.

• Do not force-fit if flange bolt pattern or intake spacing differs—verify dimensions first.
• Periodically clean jets and float bowl to prevent clogging from varnished fuel or debris.
• Replace gaskets and inspect linkage for wear during routine maintenance.

Who is this for: This YAMAKATO 27mm carburetor kit is aimed at DIY mechanics, hobbyists and small-equipment owners who need a reliable replacement or performance-oriented carburetor for mini bikes, go-karts, ATVs, pressure washers, snow blowers, tillers and similar single-cylinder machines. It's especially useful for anyone who wants a wider selection of main jets for precise tuning across different altitudes and loads. If you run a generator, confirm compatibility before buying.