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
-
On Sale
COMETIC Dipstick Cover O-Ring C9485
COMETIC
Now: $4.77Was: $5.30A degraded dipstick cover o-ring compromises your engine's sealing integrity, allowing contaminants and moisture to infiltrate your oil pan. COMETIC's C9485 replaces worn or damaged o-rings with a...09350214- SKU:
- 09350214
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- DIPSTICK COVER
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
Now: $4.77Was: $5.30 -
On Sale
COMETIC Mainshaft Seal - Big Twin C9513
COMETIC
Now: $18.99Was: $21.10A leaking mainshaft seal compromises engine integrity and leads to costly fluid loss and potential drivetrain damage. The COMETIC Mainshaft Seal for Big Twin applications delivers a precise,...09350212- SKU:
- 09350212
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- MAIN CRANKSHAFT
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- STREET
- MATERIAL:
- VITON
- UNITS:
- 5 PACK
Now: $18.99Was: $21.10 -
On Sale
COMETIC Internal Manifold Seal C9290
COMETIC
Now: $14.22Was: $15.80Cometic's internal manifold seal eliminates unwanted air leakage at the intake manifold interface, ensuring accurate fuel metering and consistent combustion chamber conditions. A properly sealed...09350156- SKU:
- 09350156
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- SEAL
- UNITS:
- 10 PACK
- APPLICATION:
- INTAKE MANIFOLD TO CARBURETOR
- MATERIAL:
- NITRILE RUBBER
- RIDING STYLE:
- STREET
Now: $14.22Was: $15.80Qty in Cart: 0Quantity:Price:Now: $14.22Was: $15.80Subtotal: -
On Sale
COMETIC Starter to Primary Case O-Ring Pack C9201
COMETIC
Now: $10.17Was: $11.30A failed starter-to-primary case seal is one of the easiest ways to turn a reliable engine into an oil-weeping liability. COMETIC's O-ring pack replaces worn or degraded seals that compromise...09350155- SKU:
- 09350155
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- STARTER
- RIDING STYLE:
- STREET
- MATERIAL:
- NITRILE RUBBER
- PRODUCT NAME:
- O-RING
- UNITS:
- 5 PACK
Now: $10.17Was: $11.30Qty in Cart: 0Quantity:Price:Now: $10.17Was: $11.30Subtotal: -
On Sale
COMETIC Crank Sensor O-Ring C9667
COMETIC
MSRP: $2.95Now: $2.88Was: $3.20Crank sensor O-rings fail silently, causing misfires, rough idle, and limp-mode diagnostics that waste hours of troubleshooting. The COMETIC C9667 replaces worn seals with a fuel-resistant design...09350153- SKU:
- 09350153
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
- APPLICATION:
- CRANKSHAFT POSITION SENSOR
- PRODUCT NAME:
- O-RING
- UNITS:
- 25 PACK
MSRP: $2.95Now: $2.88Was: $3.20Qty in Cart: 0Quantity:Price:MSRP: $2.95Now: $2.88Was: $3.20Subtotal: -
On Sale
COMETIC Case Dowel O-Ring C9287
COMETIC
Now: $8.55Was: $9.50Engine case dowel o-rings are critical sealing components that prevent oil weeping and maintain precise case alignment—failure here compromises both performance and engine longevity. The COMETIC...09350152- SKU:
- 09350152
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- STREET
- APPLICATION:
- ENGINE CASE DOWEL
- UNITS:
- 10 PACK
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
Now: $8.55Was: $9.50 -
On Sale
COMETIC Base Dowel O-Ring C9438
COMETIC
Now: $4.77Was: $5.30Proper base dowel sealing is critical to maintaining compression and preventing oil weeping at the block interface—especially under high boost or sustained RPM. The COMETIC Base Dowel O-Ring C9438...09350151- SKU:
- 09350151
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- ENGINE CASE DOWEL
- MATERIAL:
- VITON
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
- PRODUCT NAME:
- O-RING
Now: $4.77Was: $5.30 -
On Sale
COMETIC O-Ring C9292
COMETIC
Now: $14.58Was: $16.20Cometic O-Ring gaskets are engineered for critical sealing applications where leakage means lost performance and costly downtime. Whether you're building a high-boost engine or maintaining precision...09350149- SKU:
- 09350149
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- UPPER PUSHROD
- UNITS:
- 25 PACK
- MATERIAL:
- VITON
- PRODUCT NAME:
- O-RING
- RIDING STYLE:
- STREET
Now: $14.58Was: $16.20 -
On Sale
COMETIC Rocker Umbrella Seal C9633
COMETIC
Now: $27.99Was: $31.10Rocker cover seals take a beating from engine heat, oil exposure, and constant thermal cycling—premature failure means oil leaks, contamination, and potential engine bay damage. The COMETIC Rocker...09350146- SKU:
- 09350146
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- RIDING STYLE:
- STREET
- APPLICATION:
- ROCKER COVER
- APPLICATION:
- UMBRELLA VALVE
- MATERIAL:
- VITON
- PRODUCT NAME:
- SEAL
- UNITS:
- 10 PACK
Now: $27.99Was: $31.10Qty in Cart: 0Quantity:Price:Now: $27.99Was: $31.10Subtotal: -
On Sale
COMETIC Complete Engine/Primary Gasket Set C10269
COMETIC
MSRP: $340.15Now: $306.14Was: $340.15A complete gasket set is foundational to engine reliability—without proper sealing, combustion pressure escapes, coolant leaks, and oil weeps compromise both performance and longevity. The COMETIC...09346331- SKU:
- 09346331
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- RIDING STYLE:
- STREET
- TYPE:
- COMPLETE
- UNITS:
- KIT
- BORE SIZE:
- 3,937'
- PRODUCT NAME:
- GASKET
MSRP: $340.15Now: $306.14Was: $340.15Qty in Cart: 0Quantity:Price:MSRP: $340.15Now: $306.14Was: $340.15Subtotal: -
On Sale
COMETIC Motor Gasket Kit - M8 C10256
COMETIC
MSRP: $267.70Now: $240.93Was: $267.70A failed gasket kit can cost you a race and thousands in engine damage. The COMETIC M8 C10256 EST (Extreme Sealing Technology) kit eliminates hot spots and combustion leaks with precision-engineered...09346328- SKU:
- 09346328
- Availability:
- Ships Same Business Day
- Weight:
- 0.96 LBS
- BORE SIZE IMPERIAL:
- 4.250'
- RIDING STYLE:
- STREET
- BORE SIZE:
- 4,250'
- TYPE:
- COMPLETE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
MSRP: $267.70Now: $240.93Was: $267.70 -
On Sale
COMETIC Motor Gasket Kit - M8 C10252
COMETIC
MSRP: $259.30Now: $233.37Was: $259.30A reliable motor gasket kit is the foundation of a bulletproof top-end rebuild. The COMETIC M8 C10252 uses Extreme Sealing Technology to eliminate hot spots and gasket failure—critical when you're...09346327- SKU:
- 09346327
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- BORE SIZE IMPERIAL:
- 4.075'
- RIDING STYLE:
- STREET
- TYPE:
- COMPLETE
- BORE SIZE:
- 4,075'
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
MSRP: $259.30Now: $233.37Was: $259.30 -
On Sale
COMETIC Exhaust Gasket - Evo/Twin Cam/M8 C9247
COMETIC
Now: $41.40Was: $46.00A failed exhaust gasket compromises engine sealing, reduces performance, and risks catastrophic damage under sustained boost or high RPM conditions. The COMETIC C9247 delivers proven reliability...09346318- SKU:
- 09346318
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- RIDING STYLE:
- STREET
- TYPE:
- EXHAUST
- MATERIAL:
- GRAPHITE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- MATERIAL:
- STAINLESS STEEL
Now: $41.40Was: $46.00 -
On Sale
COMETIC Transmission/Engine Gasket C10214
COMETIC
MSRP: $12.95Now: $11.66Was: $12.95Transmission and engine gasket integrity is non-negotiable when you're building a reliable power plant. The COMETIC C10214 delivers the seal quality that separates a bulletproof build from a...09345981- SKU:
- 09345981
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- TYPE:
- ENGINE
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- TYPE:
- TRANSMISSION
MSRP: $12.95Now: $11.66Was: $12.95Qty in Cart: 0Quantity:Price:MSRP: $12.95Now: $11.66Was: $12.95Subtotal: -
On Sale
COMETIC Cylinder Head Gasket C10191
COMETIC
MSRP: $61.90Now: $55.71Was: $61.90A reliable cylinder head gasket is the foundation of a sealed combustion chamber—any compromise here means potential coolant leaks, oil seepage, and catastrophic engine failure. The COMETIC C10191...09345951- SKU:
- 09345951
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- THICKNESS IMPERIAL:
- 0,040'
- MATERIAL:
- LAYERED STEEL
- TYPE:
- CYLINDER HEAD
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS METRIC:
- 1.02 MM
- UNITS:
- 2 PACK
- BORE SIZE:
- 4,250'
- BORE SIZE IMPERIAL:
- 4.250'
MSRP: $61.90Now: $55.71Was: $61.90Qty in Cart: 0Quantity:Price:MSRP: $61.90Now: $55.71Was: $61.90Subtotal: -
On Sale
COMETIC Cylinder Head Gasket C10182-030
COMETIC
MSRP: $61.90Now: $55.71Was: $61.90A quality cylinder head gasket is your engine's first line of defense against catastrophic coolant and combustion leaks. The COMETIC C10182-030 delivers the reliability you need with a...09345949- SKU:
- 09345949
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- BORE SIZE IMPERIAL:
- 4.320'
- RIDING STYLE:
- STREET
- MATERIAL:
- LAYERED STEEL
- PRODUCT NAME:
- GASKET
- UNITS:
- 2 PACK
- BORE SIZE:
- 4,320'
- THICKNESS IMPERIAL:
- 0,030'
- THICKNESS METRIC:
- 0.76 MM
- TYPE:
- CYLINDER HEAD
MSRP: $61.90Now: $55.71Was: $61.90 -
On Sale
COMETIC Cylinder Head/Base Gasket C10181-HB
COMETIC
MSRP: $79.75Now: $71.78Was: $79.75A reliable cylinder head gasket is critical to maintaining compression integrity and preventing coolant/oil seepage—issues that compromise engine performance and longevity. The COMETIC C10181-HB uses...09345945- SKU:
- 09345945
- Availability:
- Ships Same Business Day
- Weight:
- 0.45 LBS
- THICKNESS IMPERIAL:
- 0,014'
- THICKNESS IMPERIAL:
- 0,040'
- THICKNESS METRIC:
- 1.02 MM
- BORE SIZE:
- 4,250'
- MATERIAL:
- LAYERED STEEL
- THICKNESS METRIC:
- 0.36 MM
- THICKNESS:
- 0,36 MM (0,014')
- TYPE:
- CYLINDER HEAD
- BORE SIZE IMPERIAL:
- 4.250'
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- THICKNESS:
- 1,02 MM (0,040')
- TYPE:
- CYLINDER BASE
- UNITS:
- KIT
MSRP: $79.75Now: $71.78Was: $79.75 -
On Sale
COMETIC Upper Rocker Box Gasket C10179-2
COMETIC
MSRP: $26.20Now: $23.58Was: $26.20A leaking rocker box gasket means oil seepage, contamination risk, and potential engine damage—this COMETIC gasket seals the deal with precision engineering that withstands high heat and pressure...09345942- SKU:
- 09345942
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- TYPE:
- ROCKER BOX
- MATERIAL:
- VITON
- MOUNTING POSITION:
- UPPER
- THICKNESS IMPERIAL:
- 0,020'
- THICKNESS METRIC:
- 0.51 MM
- UNITS:
- 2 PACK
- THICKNESS:
- 0,51 MM (0,020')
MSRP: $26.20Now: $23.58Was: $26.20 -
On Sale
COMETIC Upper Rocker Box Gasket C10179
COMETIC
Now: $61.11Was: $67.90Rocker box gaskets are critical sealing components that prevent oil leakage and maintain proper engine bay cleanliness on high-performance builds. The COMETIC C10179 combines a precision stainless...09345941- SKU:
- 09345941
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- MATERIAL:
- VITON
- TYPE:
- ROCKER BOX
- THICKNESS IMPERIAL:
- 0,020'
- THICKNESS METRIC:
- 0.51 MM
- MOUNTING POSITION:
- UPPER
- THICKNESS:
- 0,51 MM (0,020')
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- UNITS:
- 10 PACK
Now: $61.11Was: $67.90Qty in Cart: 0Quantity:Price:Now: $61.11Was: $67.90Subtotal: -
On Sale
COMETIC Cylinder Base Gasket Pair C10177-020
COMETIC
MSRP: $33.55Now: $30.20Was: $33.55A quality cylinder base gasket is foundational to maintaining proper compression and preventing coolant seepage in high-demand engines. The COMETIC C10177-020 uses multi-layer steel construction with...09345939- SKU:
- 09345939
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- MATERIAL:
- STEEL
- THICKNESS METRIC:
- 0.51 MM
- UNITS:
- 2 PACK
- MATERIAL:
- VITON
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- STREET
- TYPE:
- CYLINDER BASE
- THICKNESS IMPERIAL:
- 0,020'
MSRP: $33.55Now: $30.20Was: $33.55
