Harley Engine Gaskets and Kits
Harley Bike Gaskets & Kits at JJ Motorsports
Rebuild your Harley with premium gasket kits and seals from JJ Motorsports, featuring complete top-end, motor, and cam-install kits for leak-free performance on Milwaukee-Eight, Twin Cam, Evo, and Big Twin engines. These high-quality MLS, rubber, and metal gaskets ensure perfect sealing and long-term reliability.
Shop Feuling, Cometic, and James Gasket for proven sealing solutions. Explore related categories such as Harley engine for cams and lifters, or Harley for oil pumps and heads to complete your rebuild.
Top Harley Gaskets & Kits
- Feuling Top-End Cam Install Kit M8 2030 – Complete top-end gasket kit for Milwaukee-Eight; includes head, base, rocker, and pushrod seals.
- Cometic Complete Gasket Kit C9748F – Full engine gasket set with MLS head gaskets; fits Twin Cam 88/96/103 engines.
- James Gasket Motor Gasket Metal Base Rocker 17041-92-A – Metal rocker box base gasket set; OEM-style for Evo and Twin Cam rocker boxes.
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!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
-
COMETIC Lower Rocker Cover Rubber Gasket C9280
COMETIC
$20.10A leaking rocker cover gasket compromises engine sealing and invites oil contamination into your combustion chamber—a fast path to performance loss and engine damage. The COMETIC Lower Rocker Cover Rubber Gasket delivers OEM-grade sealing with superior...09350224- SKU:
- 09350224
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- GASKET
- MATERIAL:
- VITON
- UNITS:
- 5 PACK
- MOUNTING POSITION:
- LOWER
- MOUNTING POSITION:
- OUTER
- RIDING STYLE:
- STREET
- TYPE:
- ROCKER BOX
$20.10 -
COMETIC Head Gasket - Big Twin C10120
COMETIC
$61.90A head gasket is only as reliable as its ability to maintain a consistent seal under extreme combustion pressures and temperature cycling—and the COMETIC C10120 is engineered to deliver exactly that. This Multi-Layer Steel (MLS) design uses strategically...09344739- SKU:
- 09344739
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
- BORE SIZE:
- 3,875'
- MATERIAL:
- LAYERED STEEL
- BORE SIZE IMPERIAL:
- 3.875'
- TYPE:
- CYLINDER HEAD
- PRODUCT NAME:
- GASKET
- THICKNESS:
- 1,02 MM (0,040')
- UNITS:
- PAIR
$61.90 -
COMETIC Complete Gasket Kit - Big Twin C10121
COMETIC
$169.00A complete gasket kit is the foundation of engine reliability—especially in Big Twin applications where sustained performance demands perfect sealing. The COMETIC C10121 eliminates the guesswork of sourcing individual gaskets by delivering OEM-quality...09344740- SKU:
- 09344740
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- BORE SIZE:
- 4,125'
- BORE SIZE IMPERIAL:
- 4.125'
- UNITS:
- KIT
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
- MATERIAL:
- STEEL
- TYPE:
- MOTOR
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
$169.00Qty in Cart: 0Quantity:Price:$169.00Subtotal: -
COMETIC Complete Gasket Kit - Big Twin C10121-036
COMETIC
$169.00A complete gasket failure can sideline your Big Twin engine indefinitely, costing you race time and credibility. The COMETIC Complete Gasket Kit delivers OEM-equivalent sealing across all critical surfaces using domestic-engineered materials built for...09344741- SKU:
- 09344741
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- BORE SIZE:
- 4,125'
- TYPE:
- MOTOR
- UNITS:
- KIT
- MATERIAL:
- STEEL
- THICKNESS IMPERIAL:
- 0,036'
- BORE SIZE IMPERIAL:
- 4.125'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- THICKNESS METRIC:
- 0.91 MM
- RIDING STYLE:
- STREET
$169.00Qty in Cart: 0Quantity:Price:$169.00Subtotal: -
COMETIC Head Gasket C10037
COMETIC
$61.90A head gasket failure can sideline your engine and drain your wallet—the COMETIC C10037 prevents catastrophic leaks by maintaining a consistent seal across harsh operating conditions and high combustion pressures. The Multi-Layer Steel (MLS) construction...09344650- SKU:
- 09344650
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- BORE SIZE:
- 3,8125'
- THICKNESS:
- 1,02 MM (0,040')
- THICKNESS IMPERIAL:
- 0,040'
- TYPE:
- CYLINDER HEAD
- BORE SIZE IMPERIAL:
- 3.8125'
- THICKNESS METRIC:
- 1.02 MM
- UNITS:
- PAIR
- MATERIAL:
- LAYERED STEEL
$61.90 -
COMETIC Cylinder Base Gasket C10038
COMETIC
$33.55A quality cylinder base gasket is critical to maintaining compression integrity and preventing oil seepage in your Sportster engine. The COMETIC C10038 is engineered to withstand the thermal cycles and pressure demands of both street and track...09344651- SKU:
- 09344651
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- BORE SIZE IMPERIAL:
- 3.8125'
- THICKNESS IMPERIAL:
- 0,020'
- RIDING STYLE:
- STREET
- THICKNESS:
- 0,51 MM (0,020')
- MATERIAL:
- VITON
- THICKNESS METRIC:
- 0.51 MM
- PRODUCT NAME:
- GASKET
- TYPE:
- CYLINDER BASE
- UNITS:
- PAIR
$33.55 -
COMETIC Top End Gasket - XL1200 C9219
COMETIC
$142.75Top-end gasket failure can sideline your bike at the worst possible moment—and replacing individual gaskets piecemeal wastes time and money. The COMETIC EST gasket kit eliminates guesswork by bundling every seal, gasket, and O-ring you need for a...09341664- SKU:
- 09341664
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- DISPLACEMENT:
- 1200 CC
- MATERIAL:
- RUBBER
- TYPE:
- TOP END
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
- BORE SIZE:
- 3,8125'
- BORE SIZE IMPERIAL:
- 3.8125'
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
$142.75 -
COMETIC Breather Gasket - Twin Cam C9579
COMETIC
$8.20A failing breather gasket compromises crankcase ventilation and invites oil leakage around your cover—both problems that degrade engine performance and create messy maintenance headaches. The COMETIC C9579 delivers OEM-quality sealing with superior...09341332- SKU:
- 09341332
- Availability:
- Ships Same Business Day
- Weight:
- 0.07 LBS
- RIDING STYLE:
- STREET
- THICKNESS:
- 0,79 MM (0,031')
- THICKNESS METRIC:
- 0.79 MM
- MATERIAL:
- FIBER
- PRODUCT NAME:
- GASKET
- UNITS:
- 10 PACK
- THICKNESS IMPERIAL:
- 0,031'
- TYPE:
- BREATHER
$8.20 -
COMETIC Breather Filter - Twin Cam C9679
COMETIC
$12.00A clean breather system is critical to maintaining engine longevity and preventing crankcase pressure buildup that can compromise seals and gaskets. The COMETIC Breather Filter C9679 is a direct replacement element engineered to keep contaminants out of...09341333- SKU:
- 09341333
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- FOAM
- TYPE:
- BREATHER
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET
- UNITS:
- 10 PACK
$12.00 -
COMETIC Breather Baffle Gasket C9580
COMETIC
$8.20A worn or damaged breather baffle gasket compromises crankcase ventilation efficiency, allowing pressure buildup and potential oil leakage that can damage seals and contaminate your engine bay. The COMETIC C9580 is a direct replacement gasket engineered...09341334- SKU:
- 09341334
- Availability:
- Ships Same Business Day
- Weight:
- 0.08 LBS
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 0.79 MM
- MATERIAL:
- FIBER
- PRODUCT NAME:
- GASKET
- THICKNESS:
- 0,79 MM (0,031')
- UNITS:
- 10 PACK
- THICKNESS IMPERIAL:
- 0,031'
- TYPE:
- BREATHER
$8.20Qty in Cart: 0Quantity:Price:$8.20Subtotal: -
COMETIC Lifter Cover Gasket - Twin Cam C9578F
COMETIC
$5.40A failing lifter cover gasket leads to oil seepage, potential engine contamination, and costly internal damage if left unchecked. The COMETIC C9578F is precision-engineered to seal properly under high heat and pressure cycles, giving you reliable leak...09341335- SKU:
- 09341335
- Availability:
- Ships Same Business Day
- Weight:
- 0.07 LBS
- MOUNTING POSITION:
- FRONT
- MOUNTING POSITION:
- REAR
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0.032'
- THICKNESS METRIC:
- 0.81 MM
- TYPE:
- TAPPET BLOCK
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS:
- 0,81 MM (0,032')
- UNITS:
- 10 PACK
$5.40Qty in Cart: 0Quantity:Price:$5.40Subtotal: -
COMETIC Exhaust Gasket - Race C9719
COMETIC
$32.10Exhaust gasket failure is one of the most common sources of air leaks that compromise engine efficiency and create costly downtime. The COMETIC C9719 Race Exhaust Gasket delivers the high-temperature reliability and precision sealing you need to keep...09341336- SKU:
- 09341336
- Availability:
- Ships Same Business Day
- Weight:
- 0.14 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- MATERIAL:
- GRAPHITE
- TYPE:
- EXHAUST
- UNITS:
- 10 PACK
$32.10 -
COMETIC Oil Pan Gasket - Dyna C9646F
COMETIC
$73.30An oil pan gasket is critical to preventing costly leaks that compromise engine health and cleanliness. The COMETIC C9646F uses a proven Aluminum Foamette construction that eliminates the need for messy gasket sealer while delivering reliable, long-term...09341338- SKU:
- 09341338
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- UNITS:
- 10 PACK
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
- TYPE:
- OIL PAN
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- RIDING STYLE:
- STREET
- TYPE:
- TRANSMISSION
$73.30 -
COMETIC Oil Pan Gasket - FLT C9647F
COMETIC
$73.30Oil pan gaskets are critical sealing components that prevent leaks and maintain proper oil containment under varying engine temperatures and pressures. The COMETIC C9647F uses advanced Aluminum Foamette construction to deliver superior sealing...09341339- SKU:
- 09341339
- Availability:
- Ships Same Business Day
- Weight:
- 0.54 LBS
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- TYPE:
- OIL PAN
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
- TYPE:
- TRANSMISSION
$73.30 -
COMETIC Primary Gasket C9179F5
COMETIC
$120.50A primary gasket failure can compromise your entire engine's sealing integrity, leading to oil weeping, contamination, and potential performance loss. The COMETIC Primary Gasket C9179F5 delivers the precision engineering and material quality needed for a...09341340- SKU:
- 09341340
- Availability:
- Ships Same Business Day
- Weight:
- 0.71 LBS
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS METRIC:
- 1.52 MM
- TYPE:
- PRIMARY
- UNITS:
- 5 PACK
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- RIDING STYLE:
- STREET
- MOUNTING POSITION:
- OUTER
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
$120.50Qty in Cart: 0Quantity:Price:$120.50Subtotal: -
COMETIC Oil Change Gasket Kit C10156
COMETIC
$14.95A quality oil change gasket kit is foundational to preventing leaks and maintaining proper engine sealing during routine maintenance. The COMETIC C10156 uses proprietary AFM material that resists extreme temperatures and recovers its shape consistently,...09345073- SKU:
- 09345073
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
- UNITS:
- KIT
$14.95Qty in Cart: 0Quantity:Price:$14.95Subtotal: -
COMETIC Clutch Release Cover Gasket C9526F
COMETIC
$13.90A quality clutch release cover gasket is critical to preventing fluid leaks and maintaining consistent hydraulic pressure in your clutch system. The COMETIC C9526F uses a proven aluminum foamette construction that eliminates the need for messy gasket...09341384- SKU:
- 09341384
- Availability:
- Ships Same Business Day
- Weight:
- 0.17 LBS
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 0.81 MM
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS:
- 0,81 MM (0,032')
- THICKNESS IMPERIAL:
- 0,032'
- UNITS:
- 10 PACK
- TYPE:
- CLUTCH RELEASE COVER
$13.90 -
COMETIC Head Gasket - 4.125" - .030" C9910
COMETIC
$61.90A quality head gasket is non-negotiable for engine reliability, and the COMETIC C9910 delivers the precision sealing your high-performance build demands. Its multi-layer steel construction with load control embossments minimizes bore distortion while...09340789- SKU:
- 09340789
- Availability:
- Ships Same Business Day
- Weight:
- 0.34 LBS
- MATERIAL:
- LAYERED STEEL
- THICKNESS:
- 0,76 MM (0,030')
- BORE SIZE:
- 4,125'
- PRODUCT NAME:
- GASKET
- UNITS:
- PAIR
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0,030'
- TYPE:
- CYLINDER HEAD
- BORE SIZE IMPERIAL:
- 4.125'
- THICKNESS METRIC:
- 0.76 MM
$61.90 -
COMETIC Derby Cover Gasket - Twin Cam C9997F5
COMETIC
$21.30A quality derby cover gasket is essential for preventing oil seepage around your Twin Cam's primary cover, which can lead to cosmetic staining and potential drivetrain damage if left unchecked. Cometic's gaskets are manufactured to OEM tolerances with...09340788- SKU:
- 09340788
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- UNITS:
- 5 PACK
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS IMPERIAL:
- 0.060'
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.52 MM
- TYPE:
- DERBY COVER
$21.30Qty in Cart: 0Quantity:Price:$21.30Subtotal: -
COMETIC Foot Peg Stud Gasket C9401
COMETIC
$10.20Foot peg studs are a high-wear point in any racing application—repeated vibration, thermal cycling, and load stress can compromise gasket integrity and lead to oil seepage. The COMETIC C9401 is a precision-engineered replacement gasket that restores a...09350233- SKU:
- 09350233
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- RIDING STYLE:
- STREET
- THICKNESS:
- 0,025'
- THICKNESS IMPERIAL:
- 0.025'
- MATERIAL:
- VULCANIZED
- TYPE:
- SHIFTER STUD BOSS
- UNITS:
- 10 PACK
- MATERIAL:
- RUBBER
- PRODUCT NAME:
- GASKET
$10.20Qty in Cart: 0Quantity:Price:$10.20Subtotal:
Buying Guide and FAQs
Buying Guide: Factors to Consider When Choosing Harley Bike Engine Gaskets and Kits
- Compatibility: Ensure the kit fits your Harley's engine type (e.g., Milwaukee-Eight M8, Twin Cam 88/96/103, Evo, Big Twin) and model (e.g., FLHR Road King 1984-1998, FLST Heritage Softail 2006). Use the vehicle selector for year-specific matches, including bore sizes and applications to avoid sealing issues.
- Type of Use: For cam changes or top-end rebuilds, select install kits with ARP bolts; complete gasket sets suit full engine overhauls for leak-free performance in touring or street riding.
- Components and Upgrades: Choose kits with MLS head gaskets, Viton seals, AFM exhaust gaskets, ARP hardware, and O-rings. Focus on high-tech materials for heat dissipation, corrosion resistance, and reliable sealing.
- Brand and Quality: Opt for Feuling for cam install kits with Koyo bearings, Cometic for EST gasket sets with embossed steel, James Gasket for rocker/base gaskets, Vance & Hines for exhaust ports, or Drag Specialties for transmission boards. Prioritize USA-made quality for durability in extreme conditions.
- Installation and Cost: Kits are designed for DIY or professional rebuilds with included components like moly paste and Loctite. Prices range from $16.95 for exhaust gaskets to $356.95 for complete sets—factor in bore sizes and free shipping over $99 for value.
Frequently Asked Questions (FAQs)
- What Harley models and engines do these gaskets and kits support? Kits support Big Twin, Twin Cam, Evo, M8, and models like Road King, Heritage Softail—use the year/make/model filter for compatibility, including bore sizes like 3.500" to 3.8125".
- How do high-tech materials improve sealing? Materials like MLS steel, Viton-coated, and AFM provide even heat dissipation, corrosion resistance, and leak-free performance for rebuilds.
- What is typically included in a cam install kit? Feuling kits include seals, bearings, ARP bolts, moly paste, Loctite, washers, and copper gaskets for complete cam changes.
- Are these kits suitable for top-end rebuilds? Yes, Cometic and James Gasket kits focus on top-end with head/base/rocker gaskets for reliable overhauls.
- What if a kit doesn't fit my Harley? Verify engine type, bore size, and model before buying. Our returns policy allows exchanges or refunds if it doesn't match.
- Can I find related engine parts? Yes—explore pistons/rings, cylinders/heads, bearings/seals, or full rebuild kits in the Harley engine category to complete your gasket upgrade.
