Harley Engine
Harley Bike Engine Parts at JJ Motorsports
Rebuild and boost your Harley's engine with premium parts from JJ Motorsports. Our inventory features complete gasket sets, piston kits, oil filters, pushrod tubes, and coolers designed for maximum strength, leak-free sealing, and high-performance in extreme conditions. Compatible with Big Twins, Softail, Touring, and more, these components support top-end overhauls, oil management, and durability for street rides or custom builds.
Shop trusted brands like Drag Specialties for magnetic filters and Wiseco for forged pistons. Explore related categories such as Harley air and fuel for carb tuning or Harley drivetrain for transmission upgrades.
Top Harley Engine Products
- DRAG SPECIALTIES Magnetic Ring Oil Filter - Chrome - 3-1/4" 140003HP-BX18 – Captures metal particles with pressure relief.
- WISECO Piston Kit .010 .883 XL K1656 – Forged aluminum with rings, pins, and circlips for rebuilds.
- DRAG SPECIALTIES Pushrod Tube Kit Big Twin 75711 – Includes tubes, clips, cups, and springs for complete engine.
- ULTRACOOL Below Regulator Mount Oil Cooler Stainless Steel RF-2CSS – Fits S&S 111/124/143 engines with machined adapter.
- PAUGHCO Ribbed Teardrop Air Cleaner 701-200 – Chrome-plated aluminum with mini filter.
Browse our in-stock inventory below with same-day shipping and expert support. Questions? Contact us for fitment advice!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
-
COMETIC O-Ring C9445
COMETIC
$5.30Proper sealing is non-negotiable in high-performance engine builds, and the COMETIC O-Ring C9445 delivers the reliability you need to prevent costly leaks and maintain consistent compression. Whether you're assembling a precision stroker or refreshing a...09344703- SKU:
- 09344703
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- APPLICATION:
- OIL PUMP
- MATERIAL:
- NITRILE RUBBER
- UNITS:
- 10 PACK
- PRODUCT NAME:
- O-RING
- RIDING STYLE:
- STREET
$5.30 -
COMETIC Cylinder Base Gasket C9893
COMETIC
$28.30A degraded cylinder base gasket compromises compression, invites coolant seepage, and forces you into the shop for emergency repairs. The COMETIC Cylinder Base Gasket C9893 delivers OEM-grade sealing for Sportster engines, ensuring consistent compression...09344725- SKU:
- 09344725
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- LAYERED STEEL
- THICKNESS:
- 0,51 MM (0,020')
- THICKNESS IMPERIAL:
- 0,020'
- THICKNESS METRIC:
- 0.51 MM
- BORE SIZE IMPERIAL:
- 3.8125'
- PRODUCT NAME:
- GASKET
- TYPE:
- CYLINDER BASE
- UNITS:
- PAIR
- RIDING STYLE:
- STREET
$28.30 -
COMETIC Valve Stem Seal - .625" C9998-1
COMETIC
$4.95Valve stem seals are critical to preventing oil from seeping into your combustion chamber—a problem that degrades performance, increases emissions, and accelerates engine wear. The COMETIC C9998-1 delivers the reliability you need for sustained high-RPM...09344726- SKU:
- 09344726
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
- TYPE:
- VALVE STEM
- UNITS:
- EACH
$4.95 -
COMETIC Filter/Carb Gasket C9304
COMETIC
$12.70Carb and filter gasket integrity directly impacts fuel atomization and engine efficiency—any leakage compromises both performance and reliability. The COMETIC C9304 eliminates guesswork with a precision-engineered design that maintains a consistent seal...09342018- SKU:
- 09342018
- Availability:
- Ships Same Business Day
- Weight:
- 0.14 LBS
- THICKNESS METRIC:
- 1.52 MM
- TYPE:
- CARBURETOR BACKING PLATE
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS IMPERIAL:
- 0.060'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
$12.70 -
COMETIC Gasket C9196F5
COMETIC
$30.10High-temperature engine gaskets demand precision sealing without compromise. The COMETIC C9196F5 Viton gasket delivers exceptional chemical resistance and durability across a broad temperature range, making it ideal for forced induction builds, racing...09343175- SKU:
- 09343175
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- MOUNTING POSITION:
- UPPER
- MATERIAL:
- SILICONE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- ROCKER COVER
- PRODUCT NAME:
- GASKET
- UNITS:
- 5 PACK
$30.10 -
COMETIC Head Gasket - 3.875" x .030" C10081-030
COMETIC
$59.80A quality head gasket is non-negotiable for engine reliability and performance—it's the critical seal that prevents combustion blow-by and coolant leaks under extreme pressure and temperature. The COMETIC C10081-030 uses multi-layer steel construction...09343143- SKU:
- 09343143
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- THICKNESS:
- 0,76 MM (0,030')
- THICKNESS IMPERIAL:
- 0,030'
- BORE SIZE:
- 3,875'
- MATERIAL:
- VITON
- BORE SIZE IMPERIAL:
- 3.875'
- TYPE:
- CYLINDER HEAD
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 0.76 MM
- UNITS:
- PAIR
$59.80 -
COMETIC Head Gasket - 3.875" x .040" C10081-040
COMETIC
$59.80A quality head gasket is the foundation of a reliable engine seal—one leak can compromise compression, efficiency, and power output. The COMETIC C10081-040 uses Multi-Layer Steel (MLS) construction with Load Control Embossments to distribute clamping...09343144- SKU:
- 09343144
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- BORE SIZE IMPERIAL:
- 3.875'
- MATERIAL:
- VITON
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.02 MM
- UNITS:
- PAIR
- THICKNESS IMPERIAL:
- 0,040'
- BORE SIZE:
- 3,875'
- THICKNESS:
- 1,02 MM (0,040')
- TYPE:
- CYLINDER HEAD
$59.80 -
COMETIC Head Gasket - 3.937"x .040" C10083-040
COMETIC
$59.80A head gasket is your engine's first line of defense against combustion pressure, coolant leaks, and oil seepage—and choosing the right one directly impacts reliability and performance. The COMETIC C10083-040 MLS design distributes clamping load evenly...09343146- SKU:
- 09343146
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- BORE SIZE:
- 3,937'
- BORE SIZE IMPERIAL:
- 3.937'
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET
- THICKNESS METRIC:
- 1.02 MM
- UNITS:
- PAIR
- THICKNESS:
- 1,02 MM (0,040')
- THICKNESS IMPERIAL:
- 0,040'
- TYPE:
- CYLINDER HEAD
$59.80 -
COMETIC Head Gasket - 4.060" x .040" C10085-040
COMETIC
$59.80A head gasket failure can cost you an engine, and a poor seal costs you power—neither option is acceptable on the track or in your build. The COMETIC C10085-040 uses advanced MLS construction with Load Control Embossments to maintain even clamping...09343150- SKU:
- 09343150
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
- BORE SIZE IMPERIAL:
- 4.060'
- MATERIAL:
- VITON
- BORE SIZE:
- 4,060'
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS:
- 1,02 MM (0,040')
- TYPE:
- CYLINDER HEAD
- UNITS:
- PAIR
$59.80 -
COMETIC Head Gasket - 4.160" x .030" C10087-030
COMETIC
$59.80A head gasket is your engine's critical seal against combustion pressure, coolant leaks, and oil contamination—failure here means catastrophic engine damage. The COMETIC C10087-030 uses multi-layer steel construction with load control embossments to...09343153- SKU:
- 09343153
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- BORE SIZE IMPERIAL:
- 4.160'
- THICKNESS:
- 0,76 MM (0,030')
- THICKNESS IMPERIAL:
- 0,030'
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- BORE SIZE:
- 4,160'
- MATERIAL:
- VITON
- THICKNESS METRIC:
- 0.76 MM
- TYPE:
- CYLINDER HEAD
- UNITS:
- PAIR
$59.80 -
COMETIC Head Gasket - 4.250" x .030" C10088-030
COMETIC
$59.80A head gasket failure can derail your entire engine build, costing you time and money on the track or in the shop. The COMETIC C10088-030 MLS head gasket delivers reliable sealing across demanding racing applications with precision-engineered...09343155- SKU:
- 09343155
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- BORE SIZE:
- 4,250'
- BORE SIZE IMPERIAL:
- 4.250'
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 0.76 MM
- UNITS:
- PAIR
- MATERIAL:
- VITON
- THICKNESS:
- 0,76 MM (0,030')
- TYPE:
- CYLINDER HEAD
- THICKNESS IMPERIAL:
- 0,030'
$59.80Qty in Cart: 0Quantity:Price:$59.80Subtotal: -
COMETIC Engine Gasket Kit - Big Twin C10091
COMETIC
$141.70A complete gasket kit failure can leave your engine leaking, contaminated, or completely sidelined. The COMETIC C10091 Big Twin Engine Gasket Kit uses purpose-engineered materials—from Multi-Layer Steel head gaskets to Viton-coated base gaskets—ensuring...09344068- SKU:
- 09344068
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- MATERIAL:
- STEEL
- TYPE:
- MOTOR
- UNITS:
- KIT
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET KIT
$141.70 -
COMETIC Complete Gasket Kit - Softail C9221
COMETIC
$209.95A complete gasket failure can sideline your Softail and cost you thousands in engine damage. The COMETIC Complete Gasket Kit C9221 eliminates guesswork by delivering OEM-quality sealing across your entire engine in one comprehensive package. Built with...09341657- SKU:
- 09341657
- Availability:
- Ships Same Business Day
- Weight:
- 1.95 LBS
- MATERIAL:
- STEEL
- UNITS:
- KIT
- MATERIAL:
- VITON
- TYPE:
- COMPLETE
- BORE SIZE:
- 4,125'
- BORE SIZE IMPERIAL:
- 4.125'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
$209.95 -
COMETIC Complete Gasket Kit - FXD C9221-030
COMETIC
$209.95A complete gasket kit eliminates the guesswork when rebuilding or refreshing your FXD engine—you get every seal you need in one purchase, eliminating multiple orders and potential fitment mismatches. Cometic's multi-layer construction and Viton coatings...09341658- SKU:
- 09341658
- Availability:
- Ships Same Business Day
- Weight:
- 1.81 LBS
- MATERIAL:
- STEEL
- TYPE:
- COMPLETE
- UNITS:
- KIT
- BORE SIZE:
- 4,125'
- BORE SIZE IMPERIAL:
- 4.125'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- MATERIAL:
- VITON
- THICKNESS IMPERIAL:
- 0,030'
- THICKNESS METRIC:
- 0.76 MM
- RIDING STYLE:
- STREET
$209.95 -
COMETIC Complete Gasket Kit - FL C9222-030
COMETIC
$209.95A complete gasket kit eliminates the guesswork of sourcing individual sealing components—and prevents costly leaks that compromise engine reliability and performance. COMETIC's FL C9222-030 delivers OEM-quality sealing across every critical junction,...09341660- SKU:
- 09341660
- Availability:
- Ships Same Business Day
- Weight:
- 1.71 LBS
- MATERIAL:
- STEEL
- TYPE:
- COMPLETE
- UNITS:
- KIT
- MATERIAL:
- VITON
- THICKNESS IMPERIAL:
- 0,030'
- THICKNESS METRIC:
- 0.76 MM
- BORE SIZE:
- 4,125'
- BORE SIZE IMPERIAL:
- 4.125'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
$209.95 -
COMETIC Top End Gasket - Twin Cam - 4-1/8" C9976
COMETIC
$150.10If you're rebuilding a Twin Cam top end, a failed gasket can cost you serious downtime and money. The COMETIC C9976 eliminates guesswork by delivering a complete, precision-engineered gasket kit with proven heat management technology—so you seal it right...09341662- SKU:
- 09341662
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
- MATERIAL:
- RUBBER
- THICKNESS METRIC:
- 1.02 MM
- UNITS:
- KIT
- BORE SIZE:
- 4,125'
- BORE SIZE IMPERIAL:
- 4.125'
- TYPE:
- TOP END
- ENGINE TYPE:
- 4-STROKE
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- GASKET KIT
- THICKNESS METRIC:
- 0.51 MM
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0,020'
- THICKNESS IMPERIAL:
- 0,040'
$150.10 -
COMETIC Carb Back Plate Gasket C9626F
COMETIC
$13.50A carburetor back plate gasket is a critical seal that prevents fuel and air leaks between your carb and intake manifold—leaks that kill performance and create safety hazards. The COMETIC C9626F eliminates the guesswork with its proven aluminum Foamette...09341342- SKU:
- 09341342
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.52 MM
- TYPE:
- CARBURETOR BACKING PLATE
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
- UNITS:
- 10 PACK
- THICKNESS:
- 1,52 MM (0,060')
$13.50 -
COMETIC Filter Mount Gasket C9634F
COMETIC
$13.90A reliable filter mount gasket is critical to maintaining a sealed intake system and preventing vacuum leaks that degrade performance and fuel economy. The COMETIC C9634F uses a proven aluminum foamette design that eliminates the need for messy gasket...09341343- SKU:
- 09341343
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.52 MM
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS IMPERIAL:
- 0.060'
- TYPE:
- AIR FILTER
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- TYPE:
- BACKPLATE
- UNITS:
- 10 PACK
$13.90Qty in Cart: 0Quantity:Price:$13.90Subtotal: -
COMETIC Rear Tapped Gasket - Big Twin C9297F
COMETIC
$5.30A properly sealed engine is the foundation of reliable performance, and Cometic's rear tapped gasket eliminates the weak point where your Big Twin crankcase meets the transmission. This precision-engineered gasket prevents oil weeping and maintains...09341351- SKU:
- 09341351
- Availability:
- Ships Same Business Day
- Weight:
- 0.07 LBS
- THICKNESS:
- 0,81 MM (0,032')
- UNITS:
- 10 PACK
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- TYPE:
- TAPPET GUIDE
- MOUNTING POSITION:
- REAR
- RIDING STYLE:
- STREET
- THICKNESS IMPERIAL:
- 0,032'
- THICKNESS METRIC:
- 0.81 MM
$5.30 -
COMETIC Front Tappet Gasket - Big Twin C9298F
COMETIC
$6.40The COMETIC Front Tappet Gasket is engineered to eliminate oil seepage at the tappet cover, a common failure point on Big Twin engines. A compromised gasket leads to messy leaks, potential oil starvation, and costly engine damage—this OEM-quality...09341352- SKU:
- 09341352
- Availability:
- Ships Same Business Day
- Weight:
- 0.08 LBS
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS:
- 0,81 MM (0,032')
- TYPE:
- TAPPET GUIDE
- UNITS:
- 10 PACK
- THICKNESS METRIC:
- 0.81 MM
- RIDING STYLE:
- STREET
- MOUNTING POSITION:
- FRONT
- THICKNESS IMPERIAL:
- 0,032'
$6.40
