WISECO ORWI-CO506951-WX Seal Kit Bike

( Brand: Wiseco ), ( Manufacturer Part Number: ORWI-CO506951-WX ), ( Part Type: Seal )

Review WISECO Yamaha Dirt Bike Main Seal Kit fits YZ400 1977–1979

The **Wisco ORWI-CO506951-WX 1977-1979 Yamaha YZ400 Bike Seal Kit** is a meticulously engineered aftermarket solution designed to restore the critical sealing integrity of your classic Yamaha YZ400 s drivetrain and engine components, ensuring peak performance and longevity. This high-quality kit is tailored specifically for the iconic 1977 through 1979 models of the Yamaha YZ400, a legendary off-road motorcycle known for its reliability and ruggedness. The kit includes a comprehensive selection of precision-molded seals and gaskets, including the essential clutch seal, rear main seal, and other vital components that prevent oil leaks, reduce friction, and maintain optimal hydraulic function within the transmission and engine. Crafted from durable, heat-resistant materials, these seals are engineered to withstand the demanding conditions of off-road riding, high RPMs, and extreme temperatures, providing a reliable barrier against contamination and wear. Whether you're restoring a vintage YZ400 for track days, trail riding, or classic bike shows, this kit ensures that your bike operates smoothly and efficiently, eliminating the frustration of persistent leaks and maintaining the original performance characteristics of this timeless machine. Perfect for both DIY enthusiasts and professional mechanics, the Wiseco ORWI-CO506951-WX kit offers a direct-fit replacement that adheres to OEM specifications, allowing for easy installation and confidence in the long-term durability of your Yamaha s drivetrain.

### Pros and Cons of buying a WISECO ORWI-CO506951-WX 1977-1979 Yamaha YZ400 Bike Seal Kit

1. **Direct Fitment** This seal kit is specifically designed for the 1977-1979 Yamaha YZ400, ensuring compatibility without the need for modifications. This reduces the risk of improper installation and potential damage to the bike.

2. **High-Quality Materials** WISECO is known for producing durable, high-performance seals and gaskets that are designed to withstand the stresses of off-road use. The materials are typically resistant to heat, oil, and wear, which extends the lifespan of the components they seal.

3. **Prevents Leaks and Contamination** The primary purpose of these seals is to prevent oil, coolant, or other fluids from leaking out of critical areas like the engine, transmission, or clutch. A failing seal can lead to costly damage, so replacing them proactively can save money in the long run.

4. **Easy Installation** While some seal kits require specialized tools or experience, the WISECO kit is designed with straightforward installation in mind. It often comes with clear instructions, and the parts are typically easy to access and replace, even for intermediate DIY mechanics.

5. **Cost-Effective Solution** Replacing seals individually can be expensive, especially if multiple components fail. Buying a complete kit upfront is often cheaper than addressing individual failures as they occur. This kit provides a comprehensive solution for common wear points.

6. **Improved Performance and Reliability** Fresh seals ensure that the engine and transmission operate smoothly, reducing friction and preventing power loss due to internal leaks. This can lead to better throttle response and overall reliability, especially important for off-road riding where the bike is subjected to rough conditions.

7. **Prevents Long-Term Damage** Ignoring worn seals can lead to more severe issues, such as engine damage from oil leaks or transmission failure from contaminated fluid. Addressing seals early can prevent these costly repairs.

---

1. **Limited Availability of Parts** While this kit is designed for a specific model range, older bikes like the YZ400 may have limited aftermarket support. If you encounter issues during installation or need additional parts, sourcing them could be challenging.

2. **Potential for Counterfeit Products** Some aftermarket parts, including seal kits, are sold as counterfeit or low-quality replicas. Ensure you purchase from a reputable seller (e.g., official WISECO distributors or trusted online marketplaces) to avoid receiving substandard or fake parts.

3. **Installation Challenges** While the kit is designed for ease of use, older bikes may have rusted or seized components that complicate installation. If the seals are stuck due to corrosion, you may need to use penetrating oil, heat, or specialized tools to remove them, which could add time and effort to the process.

4. **Mixed Quality Perception** Some users report that while WISECO is generally reliable, the quality can vary depending on the specific part and batch. It s always a good idea to check reviews or ask in forums (e.g., Yamaha YZ400 owner communities) for feedback on this particular kit before purchasing.

5. **Cost Relative to New Parts** For enthusiasts who plan to restore or heavily modify their bike, the cost of this seal kit may seem high compared to purchasing new OEM parts. However, for most riders, the balance between cost and performance makes it a practical choice.

6. **Warranty Limitations** Aftermarket parts like this kit typically do not come with manufacturer warranties. If the seals fail prematurely due to defects, you may be responsible for replacement costs, though WISECO often stands by its products and offers customer support.

7. **Learning Curve for Beginners** If you re not experienced with bike maintenance, installing seals especially in tight or hard-to-reach areas can be intimidating. Mistakes during installation (e.g., improper sealing surface preparation or overtightening) can lead to leaks or damage.

---

The WISECO ORWI-CO506951-WX seal kit for the 1977-1979 Yamaha YZ400 is a practical and cost-effective solution for maintaining the reliability and performance of your bike. The kit s direct fitment, high-quality materials, and comprehensive coverage of critical seals make it a strong choice for riders looking to prevent leaks and avoid costly repairs. However, potential drawbacks such as installation challenges, the risk of counterfeit products, and limited aftermarket support for older bikes should be considered.

For most riders, the benefits outweigh the cons, especially if you re comfortable with basic mechanical work or have access to guidance during installation. If you re unsure about the process, consulting a mechanic or experienced rider before purchasing can help ensure you re making the right decision.

- You own a 1977-1979 Yamaha YZ400 and are experiencing or anticipating seal-related issues.

- You re willing to invest time in proper installation, possibly with the help of a trusted mechanic or friend with experience.

- You prioritize cost savings and long-term reliability over new OEM parts.

- You buy from a verified seller to avoid counterfeit products.

- You re a complete beginner with no mechanical experience and lack access to guidance.

- You re restoring the bike to showroom condition and prefer OEM parts for authenticity.

- You re unable to commit to the installation process due to time constraints or lack of tools.

Ultimately, this seal kit is a solid choice for maintaining your YZ400, provided you approach the installation with care and attention to detail.

Details:

Credit or Debit Card. I need to exchange an item. 1977-1979 Yamaha YZ400 Dirt Bike Wiseco Main Seal Kit: Compatibility. This is helpful if you are buying multiple items.

Parts without fitment are to be assumed universal and may require vehicle modification.: Brand: Wiseco, model Number: ORWI-CO506951-WX.

part #: orwico506951 price

• $35.08

specifications bearingmotorcycleiz:

• for models: Yz400
• for makes: Yamaha
• for years: 1977-1979
• brand: Wiseco
• mpn: Orwi-co506951-wx
• part type: Seal

payments bearingmotorcycleiz:

• wallet: Apple-pay
• other
• credit card: Diners-club

offer bearingmotorcycleiz:

• quantity: 4
• availability: In Stock
• started: March 7, 2026
• options: Ship-to-home
• sold: 0

seller bearingmotorcycleiz:

• rating: 99.8%
• # reviews: 79379
• city: Indiana, US

returns bearingmotorcycleiz:

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

shipping bearingmotorcycleiz:

• class: Standard
• type: Fixed
• service: Standard
• cost: $0.00
• transit: 4-6 Days

general bearingmotorcycleiz:

• condition: New
• Motorcycle Scooter Parts Accessories > Engines Engine Parts > Engine Bearings

Wiseco ORWI-CO506951 Is Similar To:

• 125 Exc Wiseco Ktm Top End Gasket Kit For (27% similar) ...(May 1st, 2018)
• 125 Sx Wiseco Ktm Top End Piston Gasket Kit Over For (29.5% similar) ...(September 4th, 2018)
• 125ds 125ts Wiseco Suzuki Piston Kit Over For (20.9% similar) ...(April 3rd, 2018)
• 24322b Vertex No Warranty New Wiseco Big Bore Piston Kit Pistons (25.4% similar) Big bore piston kit all skirts are coated with a hi-tech molybdenum sulphate coating for faster break-in time and increased life forged pistons increase engines displacement, torque, peak horsepower all heat treated T-5 hardening tempering cycle kits include piston, rings, wrist pin cir clips 24322B...(June 20th, 2019)
• 24367b Vertex New Wiseco Forged Replica Piston Kit (30% similar) Forged replica piston kit all skirts are coated with a hi-tech molybdenum sulphate coating for faster break-in time and increased life forged pistons from 2618 aluminum superior strength durability all heat treated T-5 hardening tempering cycle replica rings oem replacement skits include piston, ...(June 20th, 2019)
• 3150xc Wiseco Piston Ring Set Std Bore Yamaha Comp (30% similar) Piston ring set std bore 80MM yamaha XS650: 1 comp brand new. No labor is covered in warranty...(October 8th, 2018)
• 3189kd Wiseco Kawasaki Tigershark Yamaha (30.9% similar) This item is brand new and unused in its original factory packaging...(December 1st, 2017)
• 338m07050 Oversize 70.50mm Piston Honda Wiseco Kit 0.50mm (18.6% similar) 50MM 338 hon piston, Wiseco manufacturer P/N 338M07050 color size forged from high silicon aluminum alloy for maximum strength and dependability Wiseco offers a complete range of popular piston model's and years for both trail and racing applications durability, longevity and increased horsepower ...(February 13th, 2015)
• Wiseco Honda 338m07100 Oversize Piston 1.00mm 71.00mm Kit (37.2% similar) 00MM oversize to 71. 00MM 338 hon piston, Wiseco manufacturer P/N 338M07100 color size forged from high silicon aluminum alloy for maximum strength and dependability Wiseco offers a complete range of popular piston model's and years for both trail and racing applications durability, longevity and ...(January 14th, 2015)
• 369m04950 Standard Kawasaki Bore 49.50mm Piston Kit Wiseco (12.3% similar) Feel free to with any questions. Product images are for reference only. Actual product may vary. 50MM 369M04950 Kawasaki brand model 49. Wiseco piston kit standard bore 49. Some full face helmets are shown with tinted outer shield for display purposes only. 50MM 369 jaw piston, Wiseco manufacturer P...(December 28th, 2014)
• 374p4 Wiseco Piston Rings Clips Yamaha (31.5% similar) Still clean and new. But this is the same part with older. 67MM 1MM over. Eventually the part number was changed to 374M06700 by Wiseco has been in storage for years. Comes with rings 2638CD and clips CW16. New old stock. Wiseco 374P4 piston for yamaha YZ175, IT175...(August 23rd, 2018)