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 Cam Cover Gasket - Big Twin C9334F5
COMETIC
$44.00A leaking cam cover gasket compromises engine cleanliness and can lead to oil seepage onto critical components. The COMETIC Cam Cover Gasket C9334F5 delivers factory-spec sealing performance with superior material durability, eliminating the need for...20111499- SKU:
- 20111499
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.52 MM
- THICKNESS:
- 1,52 MM (0,060')
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
- TYPE:
- CAM COVER
$44.00 -
COMETIC Cam Cover Gasket - XL C9311F5
COMETIC
$53.50A failing cam cover gasket can silently sabotage your engine—leaking oil onto hot components, creating fire hazards, and compromising internal cleanliness. The COMETIC Cam Cover Gasket XL C9311F5 delivers OEM-grade sealing with superior materials and...20111501- SKU:
- 20111501
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.52 MM
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS IMPERIAL:
- 0.060'
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- TYPE:
- CAM COVER
$53.50 -
COMETIC Cam Cover Gasket - XL C9313F5
COMETIC
$48.20A failing cam cover gasket compromises engine sealing and invites oil leakage into critical ignition components—exactly what you don't need during a race or long-distance drive. COMETIC's cam cover gasket delivers the precision fit and material...20111502- SKU:
- 20111502
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- GASKET
- THICKNESS IMPERIAL:
- 0.060'
- TYPE:
- CAM COVER
- RIDING STYLE:
- STREET
- THICKNESS:
- 1,52 MM (0,060')
- THICKNESS METRIC:
- 1.52 MM
- UNITS:
- 5 PACK
$48.20 -
COMETIC Pushrod O-Ring - M8 C9586-M8
COMETIC
$15.70Pushrod seal degradation leads to oil leakage and compression loss—two problems that compromise engine reliability and performance. The COMETIC M8 Pushrod O-Ring delivers consistent sealing integrity across high-RPM cycles, protecting your engine's...09351030- SKU:
- 09351030
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- APPLICATION:
- PUSHROD TUBE
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SEAL
- UNITS:
- KIT
$15.70Qty in Cart: 0Quantity:Price:$15.70Subtotal: -
COMETIC Oil Pump Seal C10305
COMETIC
$10.95An oil pump seal failure can lead to catastrophic oil leakage, dropping pressure and starving critical engine bearings of lubrication during high-performance runs. The COMETIC Oil Pump Seal C10305 delivers OEM-grade sealing integrity with superior...09351181- SKU:
- 09351181
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- EACH
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
- TYPE:
- OIL PUMP
$10.95 -
COMETIC Valve Stem Seal C10202
COMETIC
$15.80Valve stem seals are critical to engine longevity—they prevent oil from seeping into the combustion chamber, which causes excessive smoke, oil consumption, and carbon buildup. The COMETIC C10202 uses premium, fuel-resistant elastomer compounds engineered...09350991- SKU:
- 09350991
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- PRODUCT NAME:
- SEAL
- APPLICATION:
- VALVE COVER
- RIDING STYLE:
- STREET
- UNITS:
- KIT
$15.80Qty in Cart: 0Quantity:Price:$15.80Subtotal: -
COMETIC Intake Seal C10203
COMETIC
$13.50A proper intake seal is critical to maintaining consistent air flow and preventing vacuum leaks that compromise engine efficiency and performance tuning. The COMETIC Intake Seal C10203 delivers precision engineering with domestic manufacturing quality,...09350992- SKU:
- 09350992
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- 4 PACK
- APPLICATION:
- INTAKE MANIFOLD
- RIDING STYLE:
- STREET
$13.50Qty in Cart: 0Quantity:Price:$13.50Subtotal: -
COMETIC Throttle Body Seal C10204
COMETIC
$41.10A leaking throttle body seal compromises fuel atomization and engine response, leading to inconsistent air-fuel ratios and performance loss. The COMETIC C10204 delivers a precision seal that maintains critical combustion chamber integrity, whether you're...09350993- SKU:
- 09350993
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SEAL
- APPLICATION:
- THROTTLE BODY
- UNITS:
- KIT
$41.10 -
COMETIC Neutral Indicator Washer C9497
COMETIC
$6.70The COMETIC Neutral Indicator Washer C9497 is an essential component for maintaining precise ignition timing and engine synchronization in high-performance applications. This OEM-quality washer prevents creep and misalignment that can compromise timing...09350204- SKU:
- 09350204
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- NEUTRAL GEAR SWITCH
- UNITS:
- 10 PACK
- MATERIAL:
- NYLON
- APPLICATION:
- TRANSMISSION
- THICKNESS:
- 0,063'
- THICKNESS IMPERIAL:
- 0.063'
- PRODUCT NAME:
- WASHER
- RIDING STYLE:
- STREET
$6.70 -
COMETIC Camshaft Rubber Seal C9519
COMETIC
$5.30A failing camshaft seal can silently drain your engine's oil and compromise performance when you can't afford the downtime. The COMETIC C9519 is engineered to maintain a consistent, leak-free seal across thermal cycles and extended engine run time,...09350206- SKU:
- 09350206
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- MATERIAL:
- RUBBER
- UNITS:
- 10 PACK
- PRODUCT NAME:
- SEAL
- APPLICATION:
- CAMSHAFT
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
$5.30Qty in Cart: 0Quantity:Price:$5.30Subtotal: -
COMETIC Main Shaft Seal - 5 Pack C9523
COMETIC
$16.90Main shaft seals are critical components that prevent fluid leakage and contamination in your transmission or differential housing. A compromised seal leads to fluid loss, bearing damage, and eventual drivetrain failure—downtime you can't afford. This...09350208- SKU:
- 09350208
- Availability:
- Ships Same Business Day
- Weight:
- 0.34 LBS
- MATERIAL:
- VITON
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- STREET
- APPLICATION:
- MAIN CRANKSHAFT
- UNITS:
- 5 PACK
$16.90 -
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
