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Start ShoppingMikuni F4/042-540 Hex Main Jet - 540 Orifice Size for Precision Fuel Delivery
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Description
Upgrade your carburetor's fuel delivery precision with Mikuni's F4/042-540 Hex Main Jet. This 540 orifice size jet ensures perfect fuel-air mixture for enhanced engine performance, whether you're riding a motorcycle, scooter, or ATV. The hex head design makes installation and adjustments faster than traditional jets.
Key Features
- Hex Head Design: Simplifies installation and removal without damaging the carburetor body.
- Brass Construction: Ensures durability and resistance to corrosion in harsh riding conditions.
- Standard Mikuni Thread: Compatible with all Mikuni carburetor models for seamless integration.
- 540 Orifice Size: Precisely calibrated for optimal fuel flow in high-performance engines.
Why Choose This Product
Engineers and riders trust Mikuni jets for their reliability and precision. This jet's hex design reduces installation time while maintaining a secure fit, minimizing the risk of leaks. The brass material ensures long-lasting performance even in extreme temperatures. Whether you're tuning a racing bike or optimizing your daily rider, the F4/042-540 delivers consistent fuel delivery for smoother power and better throttle response.
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Upgrade your carburetor's fuel delivery precision with Mikuni's F4/042-540 Hex Main Jet. This 540 orifice size jet ensures perfect fuel-air mixture for enhanced engine performance, whether you're riding a motorcycle, scooter, or ATV. The hex head design makes installation and adjustments faster than traditional jets.
Key Features
- Hex Head Design: Simplifies installation and removal without damaging the carburetor body.
- Brass Construction: Ensures durability and resistance to corrosion in harsh riding conditions.
- Standard Mikuni Thread: Compatible with all Mikuni carburetor models for seamless integration.
- 540 Orifice Size: Precisely calibrated for optimal fuel flow in high-performance engines.
Why Choose This Product
Engineers and riders trust Mikuni jets for their reliability and precision. This jet's hex design reduces installation time while maintaining a secure fit, minimizing the risk of leaks. The brass material ensures long-lasting performance even in extreme temperatures. Whether you're tuning a racing bike or optimizing your daily rider, the F4/042-540 delivers consistent fuel delivery for smoother power and better throttle response.
| SKU | GMAE0EF812 |
|---|---|
| MPN | F4/042-540 |
| Brand | MIKUNI |
| Category | Jets |
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Frequently Asked Questions
The number refers to the jet orifice size. Larger numbers = larger orifice = more fuel flow. The 540 is a mid-range main jet size used in various Mikuni carburetors.
You need to know your carburetor model first. Check your carb documentation or consult with a tuning specialist. Jet selection depends on altitude, temperature, engine modifications, and carburetor type.
Hex jets have a hexagonal head for easier removal/installation with a wrench or socket. Non-hex jets typically require a jet removal tool. Hex design is more convenient for maintenance.
No. Different Mikuni carburetors use different jet thread sizes and configurations. You must verify compatibility with your specific carburetor model before purchasing.
Main jets rarely wear out. Replace them only if damaged, or when tuning your carburetor for different conditions (altitude, temperature, engine modifications).
Installation Guide
Difficulty
Easy
Est. Time
15 min
Tools Required
- Hex wrench or socket matching jet head size
- Carburetor removal tools (if full carb service)
- Clean workspace
- Gasket scraper (plastic preferred)
Pro Tips
- Keep jets organized by size when doing multiple replacements
- Clean jet passages with carburetor cleaner before installing new jets
- Use a light touch when tightening - these are precision components
- Take photos before disassembly to remember jet configuration
- Consider replacing all jets (pilot, needle, main) as a set for optimal tuning
Common Mistakes to Avoid
- Over-tightening the jet, which can strip threads or crack the jet
- Installing wrong jet size for your application
- Not cleaning the jet passage before installation
- Forgetting to replace carburetor gaskets during service
Durability & Warranty
Expected Lifespan
Indefinite if not damaged. Jets are precision components that don't wear out under normal use.
Warranty
Typically covered under manufacturer warranty against defects
Maintenance
No maintenance required. Replace only if damaged or when tuning carburetor.
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