Dirt Bike Engine Gaskets and Kits
Dirt Bike Engine Gaskets & Top-End Kits for Yamaha, Honda XR650L & CRF at JJ Motorsports
Refresh your dirt bike's top end with premium engine gaskets and complete kits from JJ Motorsports, precision-manufactured for leak-free sealing, optimal compression, and reliable performance in motocross, enduro, and trail riding. Our selection includes full gasket sets, top-end rebuild kits, O-rings, and head/base gaskets designed for perfect fitment, heat resistance, and easy installation without machining. Compatible with popular models like Yamaha YZ/WR, Honda XR650L, CRF, and more, these high-quality components from trusted brands ensure smoother operation, reduced oil consumption, and extended engine life under dusty, high-RPM conditions. From Moose Racing's comprehensive off-road sets to ProX and Athena's OEM-spec top-end kits, get everything needed for a professional rebuild—head gaskets, valve seals, base gaskets, and more—to restore power and prevent blow-by on every ride.
Shop brands like Moose Racing, ProX, and Athena for race-proven quality. Explore related categories such as dirt bike piston and ring kits for full rebuilds or dirt bike engine for cylinders and valves.
Top Dirt Bike Engine Gaskets & Kits
- Moose Offroad Complete Gasket Set Yamaha 8080037MSE – Full engine gasket kit for Yamaha models; includes all necessary seals, O-rings, and gaskets for complete top-to-bottom rebuild with OEM reliability.
- ProX Top End Gasket Set Honda XR650L 35.1623 – Precision top-end kit for Honda XR650L; features head, base, and valve stem seals for leak-free compression and easy installation.
- Athena Top End Gasket Kit Honda P400210600323 – High-performance top-end rebuild kit for Honda CRF models; includes multi-layer steel head gasket, O-rings, and seals for maximum sealing under extreme conditions.
Browse our in-stock inventory below with same-day shipping and expert support. Free shipping on orders over $99! Questions? Contact us for fitment advice!
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On Sale
COMETIC Top End Gasket Kit - KTM/Husqvarna/Gas Gas C3623
COMETIC
MSRP: $46.95Now: $44.00Was: $46.95A top-end rebuild demands precision gasket sealing to contain combustion pressures and maintain ring seal—especially in high-output 4-stroke engines where even minor leakage degrades performance and reliability. The COMETIC C3623 kit delivers the exact...09347804- SKU:
- 09347804
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $46.95Now: $44.00Was: $46.95 -
On Sale
COMETIC Top End Gasket Kit - 79 mm - KTM/Husqvarna/Gas Gas C3595-EST
COMETIC
MSRP: $87.95Now: $83.00Was: $87.95A top-end gasket failure can sideline your bike mid-season, and inferior gaskets invite compression loss, oil leaks, and catastrophic engine damage. The COMETIC EST gasket kit eliminates guesswork with precision-engineered sealing surfaces and...09347806- SKU:
- 09347806
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $87.95Now: $83.00Was: $87.95 -
On Sale
COMETIC Top End Gasket Kit - 90 mm - KTM/Husqvarna/Gas Gas C3790
COMETIC
MSRP: $97.95Now: $92.00Was: $97.95A worn or failing top-end gasket kit compromises combustion sealing and invites coolant or oil leakage—both costly problems for high-performance engines. The COMETIC C3790 kit delivers the precision engineering needed to maintain peak cylinder pressure...09347857- SKU:
- 09347857
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $97.95Now: $92.00Was: $97.95 -
On Sale
COMETIC Top End Gasket Kit - Kawasaki C3803
COMETIC
MSRP: $84.95Now: $80.00Was: $84.95A failing top end gasket compromises cylinder pressure, bleeds horsepower, and risks catastrophic engine damage—especially in high-output 4-stroke engines running forced induction or extreme naturally aspirated configurations. The COMETIC C3803 Top End...09347860- SKU:
- 09347860
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $84.95Now: $80.00Was: $84.95 -
On Sale
COMETIC Top End Gasket Kit - 96 mm - Kawasaki C3806
COMETIC
MSRP: $88.95Now: $84.00Was: $88.95A quality gasket kit is non-negotiable for any top-end rebuild—it's the barrier between combustion pressures and coolant passages, and failure means catastrophic engine damage. The COMETIC C3806 uses multi-layered steel construction with Viton rubber...09347861- SKU:
- 09347861
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $88.95Now: $84.00Was: $88.95 -
On Sale
COMETIC Top End Gasket Kit - 48 mm - Kawasaki/Suzuki C7737
COMETIC
MSRP: $28.95Now: $27.00Was: $28.95A failing top end gasket compromises combustion chamber sealing, causing power loss, coolant leakage, and potential engine damage. The COMETIC C7737 kit delivers OEM-spec sealing with multi-layered steel construction and Viton rubber coating, engineered...09347867- SKU:
- 09347867
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
MSRP: $28.95Now: $27.00Was: $28.95 -
On Sale
COMETIC Top End Gasket Kit - 54.5 mm - Kawasaki C3543
COMETIC
MSRP: $31.95Now: $30.00Was: $31.95A quality top end gasket kit is critical to maintaining compression, preventing coolant and oil leaks, and ensuring reliable performance during high-output operation. The COMETIC C3543 is engineered specifically for Kawasaki applications with...09347841- SKU:
- 09347841
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
MSRP: $31.95Now: $30.00Was: $31.95 -
On Sale
COMETIC Top End Gasket Kit - 77 mm - Yamaha C3549-EST
COMETIC
MSRP: $74.95Now: $70.00Was: $74.95A failing top end gasket compromises compression, kills power, and leaves you stranded. Cometic's EST gasket kit seals high-output 4-stroke engines reliably, whether naturally aspirated or boosted, by distributing heat evenly across the sealing surface...09347842- SKU:
- 09347842
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $74.95Now: $70.00Was: $74.95 -
On Sale
COMETIC Top End Gasket Kit - 79 mm - Honda C3635
COMETIC
MSRP: $67.95Now: $64.00Was: $67.95A quality top end gasket kit is critical for maintaining cylinder pressure and preventing catastrophic coolant or oil leaks—especially when running high-horsepower naturally aspirated or forced-induction builds. The COMETIC C3635 uses multi-layered steel...09347846- SKU:
- 09347846
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $67.95Now: $64.00Was: $67.95 -
On Sale
COMETIC Top End Gasket Kit - 96 mm - Kawasaki C3696
COMETIC
MSRP: $85.95Now: $81.00Was: $85.95A failed head gasket means downtime and expensive engine damage—especially on high-output 4-stroke engines running elevated cylinder pressures. The COMETIC Top End Gasket Kit delivers the sealing integrity your engine demands, with multi-layered steel...09347848- SKU:
- 09347848
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $85.95Now: $81.00Was: $85.95 -
On Sale
COMETIC Top End Gasket Kit - 96 mm - Honda C3733
COMETIC
MSRP: $85.95Now: $81.00Was: $85.95A failing top end gasket compromises combustion sealing and allows coolant or oil to escape—both catastrophic for engine reliability and performance. This COMETIC kit delivers OEM-correct fitment with multi-layer steel construction and Viton coating,...09347850- SKU:
- 09347850
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $85.95Now: $81.00Was: $85.95 -
On Sale
COMETIC Top End Gasket Kit - KTM/Husqvarna/Gas Gas C3636
COMETIC
MSRP: $47.95Now: $45.00Was: $47.95A failed top-end gasket can cost you race time, engine damage, and thousands in repairs. The COMETIC C3636 kit delivers OEM-quality sealing with performance-grade materials engineered to handle the extreme pressures of modern 4-stroke engines. Whether...09347801- SKU:
- 09347801
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
MSRP: $47.95Now: $45.00Was: $47.95 -
On Sale
COMETIC Top End Gasket Kit - 80 mm - Yamaha C3766
COMETIC
MSRP: $79.95Now: $75.00Was: $79.95A failing top-end gasket compromises combustion chamber sealing, killing power output and risking catastrophic engine damage. The COMETIC C3766 kit delivers the precision sealing your high-output engine demands, with multi-layered construction designed...09347852- SKU:
- 09347852
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $79.95Now: $75.00Was: $79.95 -
On Sale
COMETIC Top End Gasket Kit - KTM/Husqvarna/Gas Gas C3811
COMETIC
MSRP: $79.95Now: $75.00Was: $79.95A failed top end gasket can sideline your bike and compromise engine integrity—especially when you're pushing high horsepower through naturally aspirated or forced induction setups. This Cometic kit delivers the sealing reliability you need with MLS...09347803- SKU:
- 09347803
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $79.95Now: $75.00Was: $79.95 -
On Sale
COMETIC Top End Gasket Kit - 91 mm - KTM C3784-EST
COMETIC
MSRP: $74.95Now: $70.00Was: $74.95A quality gasket kit is non-negotiable for any top-end rebuild—it's your seal against compression loss, coolant weeping, and catastrophic engine failure. The COMETIC C3784-EST delivers the sealing reliability you need with EST (Extreme Sealing...09347854- SKU:
- 09347854
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $74.95Now: $70.00Was: $74.95 -
On Sale
COMETIC Top End Gasket Kit - 97 mm - Yamaha C3786
COMETIC
MSRP: $78.95Now: $74.00Was: $78.95A failing top end gasket will compromise combustion sealing and cost you power—or worse, create catastrophic engine damage. This Cometic kit delivers the complete solution with precision-engineered gaskets designed to handle high-horsepower 4-stroke...09347855- SKU:
- 09347855
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $78.95Now: $74.00Was: $78.95 -
On Sale
COMETIC Top End Gasket Kit - 79 mm - Kawasaki C3787
COMETIC
MSRP: $84.95Now: $80.00Was: $84.95A failing head gasket will cost you power, reliability, and time on the track or in the shop. COMETIC's multi-layered steel design with Viton rubber coating distributes combustion pressure evenly across the sealing surface, reducing bore distortion and...09347856- SKU:
- 09347856
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
MSRP: $84.95Now: $80.00Was: $84.95 -
On Sale
COMETIC Top End Gasket Kit - 95 mm - KTM/Husqvarna/Gas Gas C3604-EST
COMETIC
MSRP: $74.95Now: $70.00Was: $74.95A failing top end gasket compromises combustion sealing, kills power, and invites catastrophic engine damage. The COMETIC C3604-EST delivers OEM-spec sealing reliability with advanced multi-layer construction designed for high-output 4-stroke engines...09347807- SKU:
- 09347807
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
MSRP: $74.95Now: $70.00Was: $74.95 -
On Sale
COMETIC Top End Gasket Kit - 96 mm - Honda C3801
COMETIC
MSRP: $85.95Now: $81.00Was: $85.95A failed head gasket means catastrophic engine damage and costly downtime. The COMETIC Top End Gasket Kit delivers the sealing integrity and thermal management your high-output engine demands, whether you're running naturally aspirated or forced...09347859- SKU:
- 09347859
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
MSRP: $85.95Now: $81.00Was: $85.95 -
On Sale
COMETIC Top End Gasket Kit - 88 mm - KTM/Husqvarna/Gas Gas C3810
COMETIC
MSRP: $102.95Now: $97.00Was: $102.95A top end gasket kit failure can mean catastrophic engine damage and costly downtime. Cometic's multi-layered design with EST (Extreme Sealing Technology) delivers superior heat dissipation and bore consistency, eliminating hot spots that plague stock...09347862- SKU:
- 09347862
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
MSRP: $102.95Now: $97.00Was: $102.95Qty in Cart: 0Quantity:Price:MSRP: $102.95Now: $97.00Was: $102.95Subtotal:
