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 Valve Stem Seal C9424-1
COMETIC
$4.95Valve stem seals are critical components that prevent oil from leaking past the valve guides and into the combustion chamber—a problem that leads to blue smoke, increased oil consumption, and...09350835- SKU:
- 09350835
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- EACH
- MATERIAL:
- VITON
- OUTSIDE DIAMETER IMPERIAL:
- 0.625'
- TYPE:
- VALVE STEM
- RIDING STYLE:
- STREET
$4.95 -
COMETIC Carb Backplate O-Ring C9686
COMETIC
$6.25A worn or deteriorated carb backplate O-ring can cause fuel leaks, air leaks, and performance inconsistencies that compromise your engine's tuning. The COMETIC C9686 is engineered from premium...09350373- SKU:
- 09350373
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- CARBURETOR BACKING PLATE
- RIDING STYLE:
- STREET
- MATERIAL:
- NITRILE
- UNITS:
- 10 PACK
- PRODUCT NAME:
- O-RING
$6.25Qty in Cart: 0Quantity:Price:$6.25Subtotal: -
COMETIC Valve Stem Seal C9153
COMETIC
$76.00Valve stem seals are critical to preventing oil from seeping into your combustion chambers—a problem that degrades performance, increases emissions, and accelerates engine wear. The COMETIC C9153 is...09350137- SKU:
- 09350137
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- RIDING STYLE:
- STREET
- TYPE:
- VALVE STEM
- MATERIAL:
- VITON
- UNITS:
- 25 PACK
- PRODUCT NAME:
- SEAL
$76.00 -
COMETIC Valve Stem Seal - Viton C9166
COMETIC
$24.20Valve stem seals are critical to preventing oil from seeping into your combustion chambers—a problem that degrades performance, increases emissions, and accelerates wear. The COMETIC Viton C9166...09350138- SKU:
- 09350138
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- 10 PACK
- TYPE:
- VALVE STEM
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
$24.20 -
COMETIC Oil Pump Inner Small O-Ring C9449
COMETIC
$7.40A failing oil pump seal compromises lubrication pressure across your entire engine, risking catastrophic bearing wear and sudden failure. The COMETIC Oil Pump Inner Small O-Ring (C9449) is engineered...09350159- SKU:
- 09350159
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
- APPLICATION:
- OIL PUMP
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
$7.40Qty in Cart: 0Quantity:Price:$7.40Subtotal: -
COMETIC Derby Cover O-Ring - Big Twin C9662
COMETIC
$15.40The COMETIC Derby Cover O-Ring is engineered to prevent oil leakage and maintain proper crankcase sealing on your Big Twin—critical for consistent engine performance and longevity. Built from premium...09350160- SKU:
- 09350160
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- DERBY COVER
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- O-RING
- UNITS:
- 5 PACK
- MATERIAL:
- NITRILE RUBBER
$15.40Qty in Cart: 0Quantity:Price:$15.40Subtotal: -
COMETIC Cam Support O-Ring C9631
COMETIC
$3.20Cam support o-rings are critical sealing components that prevent oil leakage and maintain pressure integrity in your engine's cam cover assembly. A compromised o-ring leads to oil weeping, potential...09350165- SKU:
- 09350165
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- CAM SUPPORT
- UNITS:
- 10 PACK
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
- RIDING STYLE:
- STREET
$3.20 -
COMETIC EFI Map Senser Seal - Twin Cam C9630
COMETIC
$12.70Engine gasket seals demand absolute reliability—even minor fuel leakage or pressure loss compromises performance and risks engine damage. The Cometic EFI Map Sensor Seal (C9630) is engineered...09350166- SKU:
- 09350166
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- CAM MANIFOLD
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
- MATERIAL:
- SILICONE
$12.70Qty in Cart: 0Quantity:Price:$12.70Subtotal: -
COMETIC Umbrella Seal C9481
COMETIC
$8.40Umbrella seals are critical for preventing oil seepage and maintaining pressure integrity in high-performance engines, especially under sustained boost and elevated operating temperatures. The...09350167- SKU:
- 09350167
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- 10 PACK
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
- APPLICATION:
- UMBRELLA VALVE
$8.40 -
COMETIC O-Ring C9459
COMETIC
$3.20Cometic O-Ring seals are engineered to withstand extreme pressures and temperature fluctuations in high-performance applications where standard gaskets fail. Whether you're building a forced...09350170- SKU:
- 09350170
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- DIPSTICK COVER
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- O-RING
- UNITS:
- 25 PACK
- APPLICATION:
- PUSHROD COVER
- MATERIAL:
- NITRILE RUBBER
$3.20 -
COMETIC Intake Manifold Seal Kit - Evolution C9131
COMETIC
$14.95Intake manifold seal degradation creates vacuum leaks that compromise fuel mixture precision and reduce engine efficiency—problems that compound over time. The COMETIC Evolution C9131 kit delivers...09350172- SKU:
- 09350172
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- INTAKE MANIFOLD TO CARBURETOR
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- PRODUCT NAME:
- SEAL
$14.95Qty in Cart: 0Quantity:Price:$14.95Subtotal: -
COMETIC Carb/Manifold Sealing Ring C9088
COMETIC
$10.95Carburetor and manifold sealing rings are critical interfaces in your fuel system—a leak or deterioration here compromises air-fuel ratios and can cause fuel seepage into your engine bay. The COMETIC...09350173- SKU:
- 09350173
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- MATERIAL:
- FIBER
- APPLICATION:
- INTAKE MANIFOLD TO CARBURETOR
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SEAL
- THICKNESS IMPERIAL:
- 0.031'
- UNITS:
- EACH
$10.95Qty in Cart: 0Quantity:Price:$10.95Subtotal: -
COMETIC Derby Cover Bolt Washer C9363
COMETIC
$5.20Derby cover bolt washers are a small but critical component that prevents fasteners from loosening due to vibration and thermal cycling—a common failure point in high-performance engines. The COMETIC...09350177- SKU:
- 09350177
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- PRODUCT NAME:
- WASHER
- UNITS:
- 5 PACK
- RIDING STYLE:
- STREET
- APPLICATION:
- DERBY COVER
$5.20Qty in Cart: 0Quantity:Price:$5.20Subtotal: -
COMETIC Starter Housing O-Ring Pack C9433
COMETIC
$5.30A leaking starter housing can compromise engine reliability and create costly downtime in the garage or on the track. COMETIC's O-ring pack delivers OEM-spec sealing with the durability to handle...09350179- SKU:
- 09350179
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- O-RING
- UNITS:
- 25 PACK
- RIDING STYLE:
- STREET
- APPLICATION:
- STARTER HOUSING
- MATERIAL:
- NITRILE RUBBER
$5.30 -
COMETIC Starter Shaft Seal C9379
COMETIC
$14.80A leaking starter shaft seal compromises engine oil integrity and increases the risk of costly internal damage. The COMETIC C9379 Starter Shaft Seal delivers OEM-quality sealing performance with...09350181- SKU:
- 09350181
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- SEAL
- APPLICATION:
- STARTER SHAFT
- UNITS:
- 5 PACK
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
$14.80 -
COMETIC Starter Shaft Seal C9509
COMETIC
$16.90A failing starter shaft seal compromises engine reliability and creates potential oil leakage at a critical junction. The COMETIC C9509 delivers precision sealing that prevents costly internal damage...09350182- SKU:
- 09350182
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- APPLICATION:
- STARTER SHAFT
- UNITS:
- 5 PACK
- PRODUCT NAME:
- SEAL
- MATERIAL:
- DUAL LIP VITON
- RIDING STYLE:
- STREET
$16.90Qty in Cart: 0Quantity:Price:$16.90Subtotal: -
COMETIC Drain Plug Washer C9498
COMETIC
$6.70A worn or degraded drain plug washer is an often-overlooked source of slow oil leaks that compound maintenance headaches over time. The COMETIC C9498 eliminates this vulnerability with a premium,...09350185- SKU:
- 09350185
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- MATERIAL:
- NYLON
- RIDING STYLE:
- STREET
- THICKNESS:
- 0,063'
- THICKNESS IMPERIAL:
- 0.063'
- UNITS:
- 10 PACK
- APPLICATION:
- DRAIN PLUG
- PRODUCT NAME:
- WASHER
$6.70 -
COMETIC Counter Shaft O-Ring C9529
COMETIC
$6.40Counter shaft seals are critical to maintaining proper engine pressurization and preventing fuel leakage in high-performance applications. The COMETIC C9529 O-Ring is engineered from premium,...09350187- SKU:
- 09350187
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- O-RING
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
- APPLICATION:
- COUNTERSHAFT
- MATERIAL:
- BUNA RUBBER
$6.40 -
COMETIC Right Mainshaft O-Ring C9495
COMETIC
$5.30A compromised mainshaft seal is a fast track to fluid leakage and catastrophic drivetrain failure. The COMETIC Right Mainshaft O-Ring (C9495) replaces worn or damaged seals with a...09350188- SKU:
- 09350188
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- UNITS:
- 25 PACK
- APPLICATION:
- MAIN DRIVE GEAR
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
- APPLICATION:
- TRANSMISSION
$5.30Qty in Cart: 0Quantity:Price:$5.30Subtotal: -
COMETIC Mainshaft Quad Seal C9361
COMETIC
$10.60Mainshaft seals are critical to preventing internal transmission fluid leakage and maintaining hydraulic pressure—especially under high-performance driving conditions where vibration and heat...09350189- SKU:
- 09350189
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- MAIN DRIVE GEAR
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- SEAL
- UNITS:
- 10 PACK
- APPLICATION:
- TRANSMISSION
$10.60
