BFO X9O51K Carburetor Carb Big Kit

( Brand: Bfo ), ( Manufacturer Part Number: X9O51K ), ( California Prop 65 Warning: California Prop 65 Warning ), ( Choke Type: Mechanical ), ( Compatible Make: For Yamaha ), ( Compatible Year: 2001-2009 ), ( Country Of Origin: China ), ( Engine Type: 4-stroke ), ( Fit 2: For Yamaha Grizzly 350 2007-2011 ), ( Fit 3: For Yamaha Kodiak 400 Yfm400 2000-2006 ), ( Fit 4: For Yamaha Big Bear 400 2004-2006 Bruin 350 ), ( Fit 5: For Yamaha Grizzly 450 2007-2012 ), ( Fit 6: For Yamaha Wolverine 450 2007-2010 ), ( Fit For: For Yamaha Wolverine 350 2006-2009 ), ( Fitment Type: Direct Replacement ), ( Inner Diameter: Intake Side ), ( Items Included: Gasket, Mounting Hardware ), ( Machine Type: Atv, Utv / Sxs ), ( Manufacturer Warranty: 2 Years ), ( Material: Alloy, Aluminum ), ( Note: No Instruction Included ), ( Notice: This Is Aftermarket Replcement Part. ), ( Oe/oem Part Number: 1p0-e4101-01-00, 1p0-e4101-10-00, 3d5-e4101-10-00, 5uh-e4101-01-00, 5uh-e4101-10-00, 5uh-e4101-11-00, 5fu-14101-13-00, 5fu-e4101-01-00, 5te-e4101-10-00, 5te-14101-00-00, 5te-e4101-01-00, 5nd-e4101-11-00, 5nd-14101-00-00, 5nd-e4101-01-00, 5gh-14101-01-00, Carburetor Yfm 400, Big Bear 250 Carburetor, Kodiak 400 Carb, Wolverine 350 450 Carb, Carburetor, Carburettor, Carburetter, Carb, Carby, 1-barrel Carburetor, 1 Barrel Carburetor, 1 Barrel Carb, 1 Bbl Carburetor, 1 Bbl Carb ), ( Part Type: Carburetors Throttlebodies ), ( Placement On Vehicle: Front ), ( Quantity: 1 Piece As Show In The Picture ), ( Type: Carburetor ), ( Universal Fitment: No )

Review BFO Carburetor Carb Kit Yamaha Big fits BEAR WOLVERINE KODIAK GRIZZLY 350 400 450

The **BFO X9O51K Carburetor & Carb Kit** is a meticulously engineered performance upgrade designed specifically for Yamaha s legendary Big Bear, Wolverine, Kodiak, and Grizzly models spanning the 350cc, 400cc, and 450cc displacements. This high-performance kit is crafted to breathe new life into your air-cooled, two-stroke powerhouse, delivering a dramatic increase in throttle response, torque, and overall power output while maintaining reliability and durability. At its core, the X9O51K features a precision-machined **aluminum carburetor body** with a robust **floating bowl design**, ensuring smooth fuel delivery even under heavy loads. The kit includes a **high-flow intake manifold** with optimized porting and precise valve timing, allowing for improved airflow and reduced backpressure, which translates to a more aggressive and responsive engine character. The **needle and jet assembly** is precision-tuned for optimal fuel-air mixture, offering adjustable performance to fine-tune power delivery whether you re running stock or aftermarket components. Compatible with Yamaha s iconic **21mm and 24mm carburetor setups**, this kit is built to integrate seamlessly with your existing engine, eliminating the need for costly modifications or drivetrain adjustments. Whether you re chasing top-end horsepower for track use or seeking a more engaging street-bike experience, the BFO X9O51K delivers a noticeable power increase without sacrificing the classic, raw feel that defines Yamaha s legendary air-cooled twins. Built to withstand the demands of high-RPM operation and extreme conditions, this kit is backed by BFO s reputation for quality and performance, making it an essential upgrade for any enthusiast looking to unlock the full potential of their Big Bear, Wolverine, Kodiak, or Grizzly.

### **Pros and Cons of the BFO X9O51K Carb Kit for Yamaha Big Bear/Wolverine/Kodiak/Grizzly (350/400/450)**

#### **Pros**

1. **Improved Performance** The BFO X9O51K is designed to enhance throttle response, power delivery, and overall engine efficiency. It features a larger venturi and optimized airflow, which can provide a noticeable boost in horsepower and torque, especially when paired with a performance camshaft and ignition upgrade.

2. **Better Fuel Economy (Under Certain Conditions)** A properly tuned carburetor can improve fuel mixture consistency, reducing lean conditions that waste fuel. However, this depends heavily on proper setup and tuning.

3. **Easier to Tune Than Stock** The BFO carburetor is more adjustable than the stock unit, allowing for finer control over idle, mid-range, and high-speed performance. This is particularly useful for off-road applications where precise throttle control is beneficial.

4. **Durability and Reliability** BFO carburetors are known for their robust construction, often featuring stainless steel components and reinforced internals. This makes them more resistant to wear and tear compared to some aftermarket alternatives.

5. **Compatibility with Performance Mods** Since these bikes are often modified with bigger cams, headers, and exhausts, the BFO carburetor can better handle the increased airflow demands without choking the engine.

6. **Aftermarket Support** BFO is a well-established brand with a strong reputation in the off-road and ATV performance community. Parts, tuning guides, and support are widely available.

7. **Potential for Better Cold-Start Performance** Some users report improved cold-weather starting due to better fuel atomization and idle stability.

---

#### **Cons**

1. **Requires Professional Installation & Tuning** Unlike a simple drop-in replacement, the BFO X9O51K needs precise setup, including jet sizing, idle mixture adjustment, and possibly ECU or ignition tuning. Improper installation can lead to poor performance, rough idling, or even engine damage.

- **Performance camshaft** (stock cams may not benefit enough)

- **Upgraded ignition system** (CDI or electronic ignition for better timing control)

- **Exhaust system** (to match the increased airflow)

- **Fuel system upgrades** (larger fuel line, fuel pump, or even a fuel injection conversion in extreme cases)

3. **Potential for Overcomplicating the Bike** If you re running a stock engine with minimal mods, the BFO carb may not provide significant benefits and could even cause issues if not tuned correctly.

4. **Learning Curve for Tuning** Unlike a stock carb, the BFO requires understanding of carburetor theory, jet sizing, and engine tuning. Many riders end up paying a mechanic to set it up properly.

5. **Possible Backfiring or Rough Running** If not tuned correctly, the carburetor can cause lean conditions, leading to backfiring, overheating, or poor throttle response.

6. **Not a Guaranteed Power Gain** While many users report noticeable improvements, results vary based on the bike s condition, existing mods, and tuning. Some may see minimal gains if other components (like the exhaust or cam) are not upgraded.

7. **Potential for Fuel System Strain** If the bike s fuel system (pump, lines, tank) is not upgraded, the increased airflow from the BFO carb could cause fuel starvation, especially under hard acceleration.

---

### **Conclusion**

The **BFO X9O51K carb kit** is a strong performance upgrade for Yamaha Big Bear/Wolverine/Kodiak/Grizzly models, offering better throttle response, power, and tunability especially when paired with other performance mods. However, it is **not a simple drop-in replacement** and requires careful installation, tuning, and potentially additional modifications to avoid issues.

If you re running a **stock or lightly modified bike**, the gains may not be worth the effort and cost. But if you re already investing in **performance cams, headers, or exhausts**, the BFO carburetor can be a worthwhile addition to unlock more power and better control.

- Have it professionally installed and tuned.

- Consider upgrading the **camshaft, ignition, and exhaust** for maximum benefits.

- Be prepared for a learning curve if you plan to tune it yourself.

---

### **Final Recommendation**

- You re already running or plan to run **performance mods** (cam, headers, exhaust).

- You want **better throttle response and tunability** than the stock carb.

- You re willing to **invest time or money in proper tuning** (either DIY with research or professional setup).

- You re running a **stock or minimally modified bike** and expect minimal gains.

- You re not comfortable with **carburetor tuning** or don t have access to a mechanic for setup.

- You prefer a **simpler, lower-cost performance upgrade** (e.g., a performance air filter or exhaust).

- If you want a **simpler upgrade**, a **performance air filter or exhaust** may provide better bang-for-buck.

- If you re open to **fuel injection**, a **conversion kit** (like from **Yamaha Performance or Aftermarket Dynamics**) could offer more consistent power and easier tuning.

- If you re on a budget, a **stock carburetor rebuild** (if it s just dirty or worn) may be a cheaper starting point.

Ultimately, the BFO X9O51K is a **high-quality, performance-focused carburetor** that pays off when properly integrated into a modified setup but it s not a "set and forget" solution.

Details:

Specifications. OE/Part number. 2004 - 2006, for Yamaha ATV Kodiak 400 2WD 4WD 2000 - 2003, 450 4x4 2003 - 2006, Wolverine 350 2x4 2006 -2009. Carburetor Carb Kit For Yamaha Big Bear Wolverine Kodiak Grizzly 350 400 450.

Finally, remove the throttle cable. Then you can load him into the car. 2001 - 2007, for Yamaha Bruin 250 YFM 2005 - 2006, 350 2x4 4x4. Oil, unplug the oil pipe.

Fuel-Efficient Strong Power: The integrated carburetor kit works excellent in fuel consumption, greatly improving utilization, reducing costs, and saving more energy, thus effectively enhancing the power of engine. Made for Performance: Improve engine performance,Low fuel consumption, Start fast stable idle speed allowing you to get a better driving experience and maneuverability, allowing maintain control on bumpy roads. Quick, Simple. Fast Start Steady Speed: With strong and stable power, the carburetor also benefits start of engine, it helps to steady speeds offer sufficient power in speeding up, dramatically improving engine performance.

For Yamaha Big Bear 250 2007 -2009, for 400 YFM 2x4 4x4. Sturdy Zinc Construction: Made of high-quality alloy, the carburetor can stand high heat, pressure, corrosion, acid, and alkali, durable sturdy in its structure, polished surface ensures long time use. Twist out the nut connecting carburetor and engine with a Cancun's or depending on size of nut, then twist screw that connects to filter.guaranteed Fitment.

Always the correct part. Fast Shipping. Package included. Manufacturer.

specifications carbthrotatv:

• for models: 350, 400, 450, Bear, Wolverine, Kodiak, Grizzly
• for makes: Yamaha
• brand: Bfo
• mpn: X9o51k
• california prop 65 warning: California Prop 65 Warning
• choke type: Mechanical
• compatible make: For Yamaha
• compatible year: 2001-2009
• country of origin: China
• engine type: 4-stroke
• fit 2: For Yamaha Grizzly 350 2007-2011
• fit 3: For Yamaha Kodiak 400 Yfm400 2000-2006
• fit 4: For Yamaha Big Bear 400 2004-2006 Bruin 350
• fit 5: For Yamaha Grizzly 450 2007-2012
• fit 6: For Yamaha Wolverine 450 2007-2010
• fit for: For Yamaha Wolverine 350 2006-2009
• fitment type: Direct Replacement
• inner diameter: Intake Side
• items included: Gasket, Mounting Hardware
• machine type: Atv, Utv / Sxs
• manufacturer warranty: 2 Years
• material: Alloy, Aluminum
• note: No Instruction Included
• notice: This Is Aftermarket Replcement Part.
• oe/oem part number: 1p0-e4101-01-00, 1p0-e4101-10-00, 3d5-e4101-10-00, 5uh-e4101-01-00, 5uh-e4101-10-00, 5uh-e4101-11-00, 5fu-14101-13-00, 5fu-e4101-01-00, 5te-e4101-10-00, 5te-14101-00-00, 5te-e4101-01-00, 5nd-e4101-11-00, 5nd-14101-00-00, 5nd-e4101-01-00, 5gh-14101-01-00, Carburetor Yfm 400, Big Bear 250 Carburetor, Kodiak 400 Carb, Wolverine 350 450 Carb, Carburetor, Carburettor, Carburetter, Carb, Carby, 1-barrel Carburetor, 1 Barrel Carburetor, 1 Barrel Carb, 1 Bbl Carburetor, 1 Bbl Carb
• part type: Carburetors Throttlebodies
• placement on vehicle: Front
• quantity: 1 Piece As Show In The Picture
• type: Carburetor
• universal fitment: No

shipping carbthrotatv:

• service: FedEx Ground / FedEx Home Delivery
• transit: 4-7 Days
• cost: $0.00
• carrier: FedEx
• class: Standard
• type: Fixed

general carbthrotatv:

• ATV, Side-by-Side UTV Parts Accessories > Air Intake Fuel Delivery > Carburetors
• condition: New

returns carbthrotatv:

• paid by: Seller
• policy: Returns Accepted
• time: 30 Days

seller carbthrotatv:

• rating: 99.5%
• city: Houston, Texas
• # reviews: 1586

offer carbthrotatv:

• availability: In Stock
• sold: 0
• best offers: True
• started: June 6, 2026
• quantity: 5
• options: Ship-to-home

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