Harley Engine Heads and Parts
Harley Bike Heads & Parts at JJ Motorsports
Unlock massive airflow and power with premium S&S cylinder heads and complete kits from JJ Motorsports, precision-machined for high-compression, big-bore builds on Twin Cam, Milwaukee-Eight, and Big Twin engines. These performance heads deliver dyno-proven gains with bolt-on convenience.
Shop S&S Cycle heads for championship-winning flow and reliability. Explore related categories such as Harley engine for valves and cams, or Harley for exhaust and pistons to complete your top-end build.
Top Harley Cylinder Heads & Kits
- S&S Cycle Cylinder Heads 106-4277 – Super Stock heads for M8; 2.120"/1.610" valves with high-flow ports for 114–131ci builds.
- S&S Cycle Cylinder Heads Twin Cam 106-3240 – Performance heads for 2006–2017 Twin Cam; massive flow for 124–131ci strokers.
- S&S Cycle Cylinder Head Kit Big Twin 90-1491 – Complete head kit with valves and springs; bolt-on power for Evo and Twin Cam 88–103 engines.
Browse our in-stock inventory below with same-day shipping and expert support. Free shipping on orders over $99! Questions? Contact us for fitment advice!
- Product
- Qty in Cart
- Quantity
- Price
- Subtotal
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On Sale
S&S CYCLE Performance Replacement Head 106-6064
S&S CYCLE
MSRP: $1,553.95Now: $1,398.56Was: $1,553.95If you're running a smaller displacement engine and leaving performance on the table, the S&S Cycle Performance Replacement Head 106-6064 delivers measurable gains in flow and compression without compromise. This fully assembled, U.S.-made head is...09300141- SKU:
- 09300141
- Availability:
- Ships Same Business Day
- Weight:
- 25.21 LBS
- DISPLACEMENT:
- 76 CC
- UNITS:
- PAIR
- COLOR/FINISH:
- BLACK
- COLOR/FINISH:
- POWDER-COATED
- MATERIAL:
- ALUMINUM
- MODEL:
- SUPER STOCK
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- CYLINDER HEAD KIT
MSRP: $1,553.95Now: $1,398.56Was: $1,553.95Qty in Cart: 0Quantity:Price:MSRP: $1,553.95Now: $1,398.56Was: $1,553.95Subtotal: -
On Sale
S&S CYCLE Valve Guide - +.001" 90-2211
S&S CYCLE
MSRP: $69.95Now: $62.96Was: $69.95Precision valve guides are fundamental to cylinder head integrity and engine longevity—especially in high-performance or frequently rebuilt applications. This S&S Cycle casting maintains critical clearance tolerances while providing the material...09262894- SKU:
- 09262894
- Availability:
- Ships Same Business Day
- Weight:
- 0.08 LBS
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- VALVE GUIDE
- UNITS:
- EACH
- OVERBORE IMPERIAL:
- OVERSIZE (+0.001')
MSRP: $69.95Now: $62.96Was: $69.95Qty in Cart: 0Quantity:Price:MSRP: $69.95Now: $62.96Was: $69.95Subtotal: -
On Sale
S&S CYCLE Valve Guide - +.002" 90-2212
S&S CYCLE
MSRP: $95.95Now: $86.36Was: $95.95Maintaining proper valve guide clearance is critical for engine longevity and consistent performance—oversized guides ensure your cylinder head can handle precision boring and honing without material compromise. The S&S Cycle +.002" valve guide delivers...09262921- SKU:
- 09262921
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- OVERBORE IMPERIAL:
- OVERSIZE (+0.002')
- PRODUCT NAME:
- VALVE GUIDE
- UNITS:
- EACH
- RIDING STYLE:
- STREET
MSRP: $95.95Now: $86.36Was: $95.95 -
On Sale
S&S CYCLE Compression Release Kit 90-4915
S&S CYCLE
MSRP: $448.95Now: $404.06Was: $448.95Cold-starting air-cooled engines is easier and more reliable with a compression release that reduces kickback and strain on your starter system. The S&S Cycle 90-4915 gives you instant control over compression during startup—whether you choose electric...20099080- SKU:
- 20099080
- Availability:
- Ships Same Business Day
- Weight:
- 1.60 LBS
- PRODUCT NAME:
- COMPRESSION RELEASE KIT
- RIDING STYLE:
- STREET
- TYPE:
- ELECTRIC
- UNITS:
- KIT
MSRP: $448.95Now: $404.06Was: $448.95 -
On Sale
S&S CYCLE Compression Release Hole Plug 90-4916
S&S CYCLE
MSRP: $24.95Now: $22.46Was: $24.95If you're running a high-performance or aftermarket cylinder head, a proper compression release hole plug is essential to maintain cylinder integrity and prevent air leaks that kill efficiency. The S&S Cycle 90-4916 is precision-engineered for custom and...20099082- SKU:
- 20099082
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- COLOR/FINISH:
- ALUMINUM
- PRODUCT NAME:
- PLUG
- RIDING STYLE:
- STREET
- TYPE:
- COMPRESSION RELEASE
- UNITS:
- EACH
MSRP: $24.95Now: $22.46Was: $24.95 -
On Sale
S&S CYCLE Cylinder Heads 900-0349
S&S CYCLE
MSRP: $1,795.95Now: $1,616.36Was: $1,795.95S&S Cycle cylinder heads deliver measurable flow improvements that unlock performance gains whether you're running stock displacement or building toward future upgrades. The fully assembled design with springs and valves gets you on the road faster,...09031292- SKU:
- 09031292
- Availability:
- Ships Same Business Day
- Weight:
- 30.20 LBS
- COLOR/FINISH:
- POWDER-COATED
- COLOR/FINISH:
- WRINKLE BLACK
- DISPLACEMENT:
- 91 CC
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- UNITS:
- PAIR
MSRP: $1,795.95Now: $1,616.36Was: $1,795.95 -
On Sale
S&S CYCLE Cylinder Heads - Twin Cam 106-4270
S&S CYCLE
MSRP: $1,995.95Now: $1,796.36Was: $1,995.95If you're looking to unlock real performance gains from your Twin Cam engine, port flow is everything—and S&S Cycle cylinder heads deliver the flow characteristics that support both immediate power and future upgrades. These fully assembled heads are...09300068- SKU:
- 09300068
- Availability:
- Ships Same Business Day
- Weight:
- 27.95 LBS
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- POWDER-COATED
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- DISPLACEMENT:
- 89 CC
- COLOR/FINISH:
- SILVER
- UNITS:
- PAIR
MSRP: $1,995.95Now: $1,796.36Was: $1,995.95Qty in Cart: 0Quantity:Price:MSRP: $1,995.95Now: $1,796.36Was: $1,995.95Subtotal: -
On Sale
S&S CYCLE Retro Top End Conversion Kit 106-1070
S&S CYCLE
MSRP: $3,995.95Now: $3,596.36Was: $3,995.95If you're running a Shovelhead and want the distinctive aesthetic of a classic Panhead without a complete engine overhaul, the S&S CYCLE Retro Top End Conversion Kit delivers authentic looks with modern reliability. This bolt-on solution swaps your top...09300089- SKU:
- 09300089
- Availability:
- Ships Same Business Day
- Weight:
- 41.00 LBS
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- TYPE:
- CYLINDER
- BORE SIZE IMPERIAL:
- STOCK BORE CYLINDER
- PRODUCT NAME:
- CONVERSION KIT
- UNITS:
- KIT
MSRP: $3,995.95Now: $3,596.36Was: $3,995.95Qty in Cart: 0Quantity:Price:MSRP: $3,995.95Now: $3,596.36Was: $3,995.95Subtotal: -
On Sale
S&S CYCLE Electrical Compression Release Unit 90-4914
S&S CYCLE
MSRP: $193.95Now: $174.56Was: $193.95Starting a high-displacement or forced-induction engine shouldn't feel like wrestling a compression spring. The S&S CYCLE Electrical Compression Release Unit eliminates the grueling hand-crank struggle by automatically venting cylinder pressure the...09300135- SKU:
- 09300135
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- UNITS:
- KIT
- TYPE:
- ELECTRIC
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- COMPRESSION RELEASE ASSEMBLY
MSRP: $193.95Now: $174.56Was: $193.95 -
On Sale
S&S CYCLE Retro Top End Conversion Kit 106-1071
S&S CYCLE
MSRP: $4,499.95Now: $4,049.96Was: $4,499.95If you're running a Shovelhead and want that classic Panhead aesthetic without sacrificing modern reliability, the S&S Cycle Retro Top End Conversion Kit delivers authentic vintage looks backed by S&S engineering. This complete bolt-on solution gives you...09300090- SKU:
- 09300090
- Availability:
- Ships Same Business Day
- Weight:
- 40.87 LBS
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- TYPE:
- CYLINDER
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.625'
- PRODUCT NAME:
- CONVERSION KIT
MSRP: $4,499.95Now: $4,049.96Was: $4,499.95 -
On Sale
S&S CYCLE Performance Replacement Head 106-3466
S&S CYCLE
MSRP: $1,559.95Now: $1,403.96Was: $1,559.95The S&S Cycle Performance Replacement Head (106-3466) delivers measurable gains in airflow and compression without sacrificing the reliability you need for sustained high-RPM operation. Built for smaller displacement engines, this head optimizes port...09300060- SKU:
- 09300060
- Availability:
- Ships Same Business Day
- Weight:
- 24.00 LBS
- COLOR/FINISH:
- POWDER-COATED
- COLOR/FINISH:
- SILVER
- MATERIAL:
- STAINLESS STEEL
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- RIDING STYLE:
- STREET
- UNITS:
- PAIR
- DISPLACEMENT:
- 82 CC
MSRP: $1,559.95Now: $1,403.96Was: $1,559.95 -
On Sale
S&S CYCLE Performance Replacement Head 106-4570
S&S CYCLE
MSRP: $1,559.95Now: $1,403.96Was: $1,559.95If you're running a smaller-displacement engine and leaving performance on the table with stock heads, the S&S CYCLE 106-4570 delivers measurable gains in flow and compression without sacrificing the reliability you need for consistent racing or spirited...09300061- SKU:
- 09300061
- Availability:
- Ships Same Business Day
- Weight:
- 24.25 LBS
- PRODUCT NAME:
- CYLINDER HEAD KIT
- DISPLACEMENT:
- 82 CC
- MATERIAL:
- STAINLESS STEEL
- COLOR/FINISH:
- BLACK
- COLOR/FINISH:
- POWDER-COATED
- MODEL:
- SUPER STOCK
- RIDING STYLE:
- STREET
- UNITS:
- PAIR
MSRP: $1,559.95Now: $1,403.96Was: $1,559.95Qty in Cart: 0Quantity:Price:MSRP: $1,559.95Now: $1,403.96Was: $1,559.95Subtotal: -
On Sale
S&S CYCLE Replacement Silicone Solenoid Caps 50-1080
S&S CYCLE
MSRP: $12.95Now: $11.66Was: $12.95S&S electronic and manual compression release kits rely on precision-engineered solenoid caps to maintain reliable ignition timing and engine performance. Over time, silicone caps degrade from heat cycling and exposure, compromising the seal and...09300041- SKU:
- 09300041
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- WHITE
- PRODUCT NAME:
- CAP
- MATERIAL:
- SILICONE
- TYPE:
- COMPRESSION RELEASE
- UNITS:
- PAIR
MSRP: $12.95Now: $11.66Was: $12.95 -
On Sale
S&S CYCLE Cylinder Head Kit - Big Twin 90-1497
S&S CYCLE
MSRP: $1,895.95Now: $1,706.36Was: $1,895.95A quality cylinder head kit is fundamental to unlocking your Big Twin's full potential—whether you're building a stroker, upgrading an aging engine, or restoring a classic. The S&S Cycle 90-1497 arrives completely assembled with premium components,...09300017- SKU:
- 09300017
- Availability:
- Ships Same Business Day
- Weight:
- 25.55 LBS
- BORE SIZE IMPERIAL:
- 3.625'
- FEATURES:
- SINGLE SPARK PLUG
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- STYLE:
- STOCK COMPRESSION
- UNITS:
- KIT
- COLOR/FINISH:
- ALUMINUM
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
MSRP: $1,895.95Now: $1,706.36Was: $1,895.95Qty in Cart: 0Quantity:Price:MSRP: $1,895.95Now: $1,706.36Was: $1,895.95Subtotal: -
On Sale
S&S CYCLE Cylinder Heads - Twin Cam 90-1106
S&S CYCLE
MSRP: $1,795.95Now: $1,616.36Was: $1,795.95S&S Cycle cylinder heads deliver measurable gains in port flow and breathing efficiency, giving you performance improvements now while preserving headroom for future upgrades. Whether you're running a stock 88" motor or pushing displacement past 103",...09300006- SKU:
- 09300006
- Availability:
- Ships Same Business Day
- Weight:
- 29.01 LBS
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- DISPLACEMENT:
- 89 CC
- COLOR/FINISH:
- POWDER-COATED
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- COLOR/FINISH:
- WRINKLE BLACK
- UNITS:
- PAIR
MSRP: $1,795.95Now: $1,616.36Was: $1,795.95Qty in Cart: 0Quantity:Price:MSRP: $1,795.95Now: $1,616.36Was: $1,795.95Subtotal: -
EASTERN MOTORCYCLE PARTS Rocker Box Stud Set - Big Twin M-4-4538
EASTERN MOTORCYCLE PARTS
$47.95Rocker box studs are critical fasteners that secure your cylinder head assembly and bear significant stress from combustion pressures and engine vibration. Using OEM-equivalent studs ensures proper clamping force, prevents head gasket failure, and...09300027- SKU:
- 09300027
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- TYPE:
- ROCKER BOX
- PRODUCT NAME:
- STUD SET
- UNITS:
- 8 PACK
- RIDING STYLE:
- STREET
$47.95 -
On Sale
S&S CYCLE Cylinder Heads - Twin Cam 106-3255
S&S CYCLE
MSRP: $1,995.95Now: $1,796.36Was: $1,995.95S&S Cycle cylinder heads unlock significant performance gains on Twin Cam engines while preserving upgrade flexibility for future modifications. These fully assembled heads deliver improved port flow and combustion efficiency, making them an essential...09300065- SKU:
- 09300065
- Availability:
- Ships Same Business Day
- Weight:
- 28.65 LBS
- COLOR/FINISH:
- POWDER-COATED
- MODEL:
- SUPER STOCK
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- UNITS:
- PAIR
- DISPLACEMENT:
- 89 CC
- COLOR/FINISH:
- SILVER
- PRODUCT NAME:
- CYLINDER HEAD KIT
MSRP: $1,995.95Now: $1,796.36Was: $1,995.95Qty in Cart: 0Quantity:Price:MSRP: $1,995.95Now: $1,796.36Was: $1,995.95Subtotal: -
On Sale
S&S CYCLE Cylinder Head Kit 90-1488
S&S CYCLE
MSRP: $1,886.95Now: $1,698.26Was: $1,886.95The S&S CYCLE Cylinder Head Kit 90-1488 delivers a complete, ready-to-install solution that eliminates the guesswork of sourcing individual components. Pre-assembled with precision valve seats, guides, and matched spring rates, this kit ensures optimal...09300133- SKU:
- 09300133
- Availability:
- Ships Same Business Day
- Weight:
- 24.24 LBS
- FEATURES:
- DUAL SPARK PLUG
- MODEL:
- SUPER STOCK
- PRODUCT NAME:
- CYLINDER HEAD KIT
- STYLE:
- STOCK COMPRESSION
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- ALUMINUM
- MATERIAL:
- IRON
- UNITS:
- KIT
- BORE SIZE IMPERIAL:
- 3.625'
- MATERIAL:
- CAST
MSRP: $1,886.95Now: $1,698.26Was: $1,886.95Qty in Cart: 0Quantity:Price:MSRP: $1,886.95Now: $1,698.26Was: $1,886.95Subtotal:
