Athena Top End Race Gasket Kit R4856-199 — Yamaha YZ85 2019-2025

Athena Top End Race Gasket Kit R4856-199 — Yamaha YZ85 2019-2025

Product Description

The Athena Top End Race Gasket Kit (R4856-199) is the essential choice for pro, semi-pro, and amateur riders who need to keep their engine performing at its peak. Designed specifically for racers who need to freshen up their top end between motos or during mid-season maintenance, this kit ensures your YZ85 maintains factory-level sealing and reliability.

Engineered for versatility, this kit includes a high-performance Multi-Layer Stainless Steel (MLSS) head gasket and multiple premium-quality base gaskets of varying thicknesses. This setup allows you to precisely optimize your engine's compression ratio, giving you the flexibility to tune your bike for standard pump gas or high-octane race fuel depending on your performance goals.

Top Features: Athena Top End Race Gasket Kit

• Race-Ready Performance: Specifically designed for frequent engine freshening and performance optimization.
• MLSS Technology: Features a top-of-the-line Multi-Layer Stainless Steel head gasket for superior heat and pressure resistance.
• Compression Tuning: Includes multiple base gaskets of varying thicknesses to fine-tune squish and compression ratios.
• Professional Grade: Built to meet the demands of competitive motocross racing and high-intensity trail riding.

Please review the detailed compatibility data below to ensure an exact fitment match for your motorcycle before finalizing your purchase.

Fitment List

Year Range	Vehicle Brand	Vehicle Model
2019-2025	Yamaha	YZ85

Frequently Asked Questions

Q: Does this kit include piston rings or needle bearings?
A: No, this is a dedicated top-end gasket kit designed for sealing components. It does not include hard parts like piston rings, wrist pin bearings, or valve stem seals.

Q: How do the different base gaskets help my performance?
A: By using different thicknesses of base gaskets, you can adjust the cylinder height to change your engine's squish clearance and compression ratio, allowing you to tailor the power delivery for either pump gas or race fuel.

Expert Pro-Tip: When using the different base gaskets to tune your compression, always use a piece of solder wire to check your squish clearance after assembly. It is the only accurate way to ensure you have sufficient clearance to avoid piston-to-head contact while maximizing combustion efficiency.

Recommended Pairings:
o Yamaha YZ85 Performance Parts
o Yamaha 2-Stroke Performance Parts
o High-Temp Assembly Lube

At Moto-House MX, we carry the best brands in motocross and off-road performance. Our team has over 40 years of experience helping riders get more out of their bikes. Every order ships fast from our Central Florida location.

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