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
-
KB PERFORMANCE Piston Kit KB266.020.3
KB PERFORMANCE
$246.95KB Performance pistons deliver the precision tolerances and superior ring seal you need for consistent power and longevity in high-performance engines. Manufactured from T-5 heat-treated 390 hypereutectic aluminum, these diamond-machined pistons maintain...DS751250- SKU:
- DS751250
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE OVERSIZE - IMPERIAL:
- +0.020'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
$246.95 -
KB PERFORMANCE Piston Kit KB266.030.3
KB PERFORMANCE
$246.95If you're building or rebuilding a high-performance engine, piston quality directly impacts ring seal, combustion efficiency, and long-term durability. KB Performance pistons are diamond-machined to extraordinarily tight tolerances—allowing you to run...DS751251- SKU:
- DS751251
- Availability:
- Ships Same Business Day
- Weight:
- 2.80 LBS
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- +0.030'
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE SIZE IMPERIAL:
- 3.498'
$246.95Qty in Cart: 0Quantity:Price:$246.95Subtotal: -
KB PERFORMANCE Piston Kit KB272.010
KB PERFORMANCE
$246.95If you're building a high-revving engine that demands precision and durability, KB Performance pistons are engineered to outperform standard OEM components through superior manufacturing tolerances and tighter fitment specifications. The T-5 heat-treated...DS751254- SKU:
- DS751254
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- PISTON HEAD SHAPE:
- REVERSE
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE OVERSIZE - IMPERIAL:
- +0.010'
- UNITS:
- KIT
$246.95 -
KB PERFORMANCE Piston Kit KB272.020
KB PERFORMANCE
$246.95KB Performance pistons deliver the precision and durability demanded by serious racers and high-output builds. Manufactured to tight tolerances and engineered for minimal piston rock, this kit enables superior ring seal and extended component...DS751255- SKU:
- DS751255
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- +0.020'
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON HEAD SHAPE:
- REVERSE
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
$246.95 -
KB PERFORMANCE Piston Kit KB297.010
KB PERFORMANCE
$246.95KB Performance pistons are engineered for racers and builders who demand tight tolerances and consistent performance across multiple heat cycles. The T-5 hypereutectic aluminum construction allows for a tighter piston-to-wall fit than standard offerings,...DS751260- SKU:
- DS751260
- Availability:
- Ships Same Business Day
- Weight:
- 2.85 LBS
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.498'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE OVERSIZE - IMPERIAL:
- +0.010'
- COMPRESSION RATIO IMPERIAL:
- 8.3:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
$246.95 -
KB PERFORMANCE Piston Kit KB297.020
KB PERFORMANCE
$246.95If you're building a high-revving engine that demands reliability and precision, KB Performance pistons are engineered to outperform standard alternatives. The diamond-machined construction and tight tolerances eliminate piston rock, deliver superior...DS751261- SKU:
- DS751261
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- UNITS:
- KIT
- COMPRESSION RATIO IMPERIAL:
- 8.3:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE OVERSIZE - IMPERIAL:
- +0.020'
- BORE SIZE IMPERIAL:
- 3.498'
$246.95 -
KB PERFORMANCE Piston Kit KB297.040
KB PERFORMANCE
$246.95If you're serious about maximizing engine performance and longevity, piston quality directly impacts your results. The KB PERFORMANCE KB297.040 delivers diamond-machined precision and tight tolerances that reduce piston rock, improve ring seal, and...DS751263- SKU:
- DS751263
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 8.3:1
- UNITS:
- KIT
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE OVERSIZE - IMPERIAL:
- +0.040'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
$246.95 -
KB PERFORMANCE Piston Kit KB272.005
KB PERFORMANCE
$234.43If you're building a high-rpm engine or refreshing a tired block, piston quality directly impacts reliability and performance. KB Performance pistons are held to tolerances most manufacturers won't match—plus or minus one gram and .0005" across the...DS751264- SKU:
- DS751264
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- PISTON HEAD SHAPE:
- REVERSE
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE OVERSIZE - IMPERIAL:
- +0.005'
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- UNITS:
- KIT
$234.43 -
KB PERFORMANCE Piston Kit - Evolution KB305.000
KB PERFORMANCE
$246.95If you're building or rebuilding a high-performance engine, piston quality directly impacts reliability, ring seal, and longevity under sustained load. KB Performance's Evolution KB305.000 kit delivers the precision tolerances and material science that...DS751265- SKU:
- DS751265
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE OVERSIZE - IMPERIAL:
- STANDARD
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 9.6:1
- UNITS:
- KIT
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
$246.95 -
KB PERFORMANCE Piston Kit - Evolution KB305.005
KB PERFORMANCE
$246.95If you're building an engine that demands precision and reliability, KB Performance pistons deliver the tight tolerances and consistent weight distribution that separate competitive builds from the rest. The diamond-machined construction and T-5...DS751266- SKU:
- DS751266
- Availability:
- Ships Same Business Day
- Weight:
- 2.80 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 9.6:1
- BORE OVERSIZE - IMPERIAL:
- +0.005'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$246.95 -
KB PERFORMANCE Piston Kit - Evolution KB305.010
KB PERFORMANCE
$246.95KB Performance's Evolution KB305.010 piston kit delivers the tight tolerances and superior ring seal that separate competitive engines from the rest. With diamond-machined precision and hypereutectic aluminum construction, these pistons minimize rock and...DS751267- SKU:
- DS751267
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- BORE SIZE IMPERIAL:
- 3.498'
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- +0.010'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- COMPRESSION RATIO IMPERIAL:
- 9.6:1
$246.95Qty in Cart: 0Quantity:Price:$246.95Subtotal: -
KB PERFORMANCE Piston Kit - Evolution KB305.020
KB PERFORMANCE
$246.95KB Performance pistons are engineered for racers and serious builders who demand precision and durability under extreme conditions. The tight tolerances and superior heat treatment of these 390 hypereutectic aluminum pistons minimize rock and maximize...DS751268- SKU:
- DS751268
- Availability:
- Ships Same Business Day
- Weight:
- 2.75 LBS
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- +0.020'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 9.6:1
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
$246.95Qty in Cart: 0Quantity:Price:$246.95Subtotal: -
KB PERFORMANCE Piston Kit - Evolution KB305.030
KB PERFORMANCE
$246.95If you're pushing your engine to the limit, piston quality directly impacts reliability, ring seal, and longevity under sustained high-RPM operation. KB Performance's Evolution KB305.030 kit delivers diamond-machined precision and tight tolerances that...DS751269- SKU:
- DS751269
- Availability:
- Ships Same Business Day
- Weight:
- 2.85 LBS
- UNITS:
- KIT
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- BORE OVERSIZE - IMPERIAL:
- +0.030'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE SIZE IMPERIAL:
- 3.498'
- COMPRESSION RATIO IMPERIAL:
- 9.6:1
$246.95 -
KB PERFORMANCE Piston Kit - Twin Cam KB348.000
KB PERFORMANCE
$295.95If you're building or rebuilding a high-performance engine, piston quality directly impacts reliability, ring seal, and longevity. KB Performance's Twin Cam KB348.000 kit delivers the precision tolerances and material science that separate track-proven...DS751281- SKU:
- DS751281
- Availability:
- Ships Same Business Day
- Weight:
- 3.00 LBS
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 9.3:1
- BORE SIZE IMPERIAL:
- 3.875'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
$295.95 -
KB PERFORMANCE Piston Kit - Twin Cam KB348.005
KB PERFORMANCE
$295.95If you're serious about extending piston life and maximizing ring seal in your Twin Cam engine, KB Performance's diamond-machined pistons deliver the precision tolerances that separate reliable builds from frequent rebuilds. The T-5 heat-treated 390...DS751282- SKU:
- DS751282
- Availability:
- Ships Same Business Day
- Weight:
- 3.05 LBS
- BORE OVERSIZE - IMPERIAL:
- +0.005'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- COMPRESSION RATIO IMPERIAL:
- 9.3:1
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.875'
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
$295.95 -
KB PERFORMANCE Piston Kit - Twin Cam KB411.005
KB PERFORMANCE
$307.95If you're running a high-performance Twin Cam engine, piston quality directly impacts your power output, engine longevity, and reliability. KB Performance pistons are precision-engineered to tighter tolerances than OEM alternatives, reducing piston rock...DS751287- SKU:
- DS751287
- Availability:
- Ships Same Business Day
- Weight:
- 3.08 LBS
- BORE OVERSIZE - IMPERIAL:
- +0.005'
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.875'
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- RIDING STYLE:
- STREET
$307.95 -
KB PERFORMANCE Piston Kit KB411.010
KB PERFORMANCE
$307.95If you're building a high-performance engine that demands tight tolerances and consistent ring seal, KB Performance pistons are engineered to deliver. The T-5 heat-treated 390 hypereutectic aluminum construction allows installation at tighter clearances...DS751288- SKU:
- DS751288
- Availability:
- Ships Same Business Day
- Weight:
- 3.20 LBS
- BORE OVERSIZE - IMPERIAL:
- +0.010'
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE SIZE IMPERIAL:
- 3.875'
- COMPRESSION RATIO IMPERIAL:
- 10.5:1
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- UNITS:
- KIT
$307.95Qty in Cart: 0Quantity:Price:$307.95Subtotal: -
KB PERFORMANCE Wrist Pin Lock Ring RRN-81
KB PERFORMANCE
$10.95Wrist pin lock rings are critical components that secure the piston pin in place, preventing catastrophic engine failure from pin movement or ejection during high-RPM operation. If you're running KB Performance pistons, using OEM-equivalent replacement...09130001- SKU:
- 09130001
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- APPLICATION:
- PISTON
- TYPE:
- LOCK RING
- PRODUCT NAME:
- WRIST PIN
- RIDING STYLE:
- STREET
- UNITS:
- 4 PACK
$10.95Qty in Cart: 0Quantity:Price:$10.95Subtotal: -
KB PERFORMANCE Piston Kit - Twin Cam 88 KB425C.STD
KB PERFORMANCE
$287.95If you're building a high-revving Twin Cam 88 engine that demands precision and longevity, KB Performance pistons are engineered to deliver tighter tolerances and superior ring seal than standard replacements. The diamond-machined construction and tight...09106087- SKU:
- 09106087
- Availability:
- Ships Same Business Day
- Weight:
- 3.01 LBS
- COMPRESSION RATIO IMPERIAL:
- 8.8:1
- UNITS:
- KIT
- BORE OVERSIZE - IMPERIAL:
- STANDARD
- BORE SIZE IMPERIAL:
- 3.750'
- PISTON HEAD SHAPE:
- FLAT TOP
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
$287.95Qty in Cart: 0Quantity:Price:$287.95Subtotal: -
KB PERFORMANCE Piston Kit - Twin Cam 88 KB425C.005
KB PERFORMANCE
$287.95If you're building a Twin Cam 88 engine that demands precision and longevity, KB Performance pistons are engineered to deliver tighter tolerances and superior ring seal that production alternatives simply cannot match. The T-5 heat-treated 390...09106088- SKU:
- 09106088
- Availability:
- Ships Same Business Day
- Weight:
- 3.01 LBS
- COMPRESSION RATIO IMPERIAL:
- 8.8:1
- PISTON MATERIAL:
- HYPEREUTECTIC ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- BORE OVERSIZE - IMPERIAL:
- +0.005'
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.750'
- PISTON HEAD SHAPE:
- FLAT TOP
$287.95
