Dirt Bike Engine
Dirt Bike Engine Parts at JJ Motorsports
Discover a full range of dirt bike engine components for rebuilding or upgrading your performance from JJ Motorsports. From crankshafts to cylinder heads and piston kits, these precision-engineered components ensure reliable performance. For additional upgrades, check out our full selection of off-road dirt bike parts to keep your engine running at peak efficiency on the track or trails.
Shop trusted brands like Wiseco for forged piston kits and K&N for high-flow oil filters. Explore related categories such as Dirt Bike Air and Fuel for intake upgrades or Dirt Bike Exhaust for complete systems.
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
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VERTEX Top End Gasket Kit - Yamaha 810601
VERTEX
$13.70A degraded top end gasket kit compromises cylinder sealing, leading to coolant leaks, compression loss, and potential engine damage. The VERTEX 810601 delivers OEM-equivalent sealing integrity with...09348034- SKU:
- 09348034
- Availability:
- Ships Same Business Day
- Weight:
- 0.08 LBS
$13.70 -
VERTEX Top End Gasket Kit - Honda 810207
VERTEX
$26.87Top-end gasket failure compromises engine sealing and can lead to oil leaks, coolant weeping, and performance loss. The VERTEX 810207 kit delivers OEM-equivalent sealing with precision-engineered...09347986- SKU:
- 09347986
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
$26.87 -
VERTEX Top End Gasket Kit - Yamaha 810639
VERTEX
$26.38A failed top-end gasket can compromise your engine's seal integrity and lead to compression loss, oil seepage, and reduced performance—especially under racing conditions. The VERTEX 810639 gasket kit...09347993- SKU:
- 09347993
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$26.38 -
VERTEX Top End Gasket Kit - Yamaha 810687
VERTEX
$79.20A failing top-end gasket kit will cost you power, reliability, and potentially catastrophic engine damage. The VERTEX 810687 delivers OEM-spec sealing across your entire top end, eliminating leaks...09347994- SKU:
- 09347994
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
$79.20 -
VERTEX Top End Gasket Kit - Honda 810259
VERTEX
$42.50A top end gasket kit is critical for any Honda engine rebuild—failed gaskets lead to compression loss, oil leaks, and catastrophic engine damage. The VERTEX 810259 kit provides all necessary gaskets...09347995- SKU:
- 09347995
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
$42.50 -
VERTEX Top End Gasket Kit - Honda 810261
VERTEX
$48.37A top-end gasket kit is essential maintenance for any Honda engine experiencing oil seepage, compression loss, or preparing for high-boost applications. VERTEX gaskets are engineered to OEM...09347997- SKU:
- 09347997
- Availability:
- Ships Same Business Day
- Weight:
- 0.12 LBS
$48.37 -
VERTEX Top End Gasket Kit - Kawasaki 810484
VERTEX
$30.75A worn or failing top-end gasket kit compromises engine sealing, leading to oil leaks, coolant seepage, and potential internal damage that compounds over time. The VERTEX Top End Gasket Kit is...09348030- SKU:
- 09348030
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$30.75 -
VERTEX Top End Gasket Kit - Kawasaki 810483
VERTEX
$31.33A top-end gasket kit is essential for maintaining a proper seal between critical engine components, preventing coolant and oil leaks that compromise engine reliability and performance. Whether you're...09348033- SKU:
- 09348033
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$31.33 -
VERTEX Top End Gasket Kit - KTM 810315
VERTEX
$26.38A failed top-end gasket can cost you race time and engine reliability. The VERTEX Top End Gasket Kit (810315) delivers OEM-quality sealing with precision-cut components engineered to handle the heat...09348019- SKU:
- 09348019
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
$26.38 -
VERTEX Top End Gasket Kit - Honda 810235
VERTEX
$38.13A compromised top-end gasket can silently rob your Honda engine of power, efficiency, and reliability—especially under high-load conditions. The VERTEX 810235 Top End Gasket Kit delivers complete...09348016- SKU:
- 09348016
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
$38.13 -
On Sale
VINTCO Crankshaft Assembly - Yamaha CR2027
VINTCO
MSRP: $419.95Now: $390.55Was: $419.95A crankshaft is the backbone of your engine's bottom end—it converts combustion energy into rotational power, and any weakness here cascades through your entire drivetrain. The VINTCO CR2027 pairs a...09210950- SKU:
- 09210950
- Availability:
- Ships Same Business Day
- Weight:
- 10.20 LBS
MSRP: $419.95Now: $390.55Was: $419.95 -
JE PISTONS Piston Kit - 13.5:1 - Kawasaki 379938
JE PISTONS
$346.99If you're running your Kawasaki engine at the edge of competition, your stock pistons won't survive—you need forged internals engineered for extreme duty. JE's 13.5:1 compression pistons deliver the...09106679- SKU:
- 09106679
- Availability:
- Ships Same Business Day
- Weight:
- 1.07 LBS
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
$346.99 -
JE PISTONS Piston Kit - 14.5:1 - Kawasaki 391920
JE PISTONS
$316.99If you're running a high-compression build or pushing your Kawasaki engine into professional competition territory, you need pistons engineered for the abuse. JE's 14.5:1 compression kit delivers the...09106680- SKU:
- 09106680
- Availability:
- Ships Same Business Day
- Weight:
- 0.78 LBS
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- COMPRESSION RATIO IMPERIAL:
- 14.5:1
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$316.99 -
On Sale
ATHENA Piston Kit with Gaskets - 95.95 mm - CRF450R P5F0960322006A
ATHENA
MSRP: $259.07Now: $233.00Was: $259.07A worn or stock piston limits your CRF450R's combustion efficiency and reliability—especially under sustained high-RPM riding or aggressive trail conditions. The ATHENA Piston Kit delivers...09031744- SKU:
- 09031744
- Availability:
- Ships Same Business Day
- Weight:
- 1.53 LBS
- BORE SIZE METRIC:
- 95.95 MM
- DISPLACEMENT:
- 450 CC
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON MATERIAL:
- FORGED
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- A
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
MSRP: $259.07Now: $233.00Was: $259.07 -
On Sale
ATHENA Piston Kit with Gaskets - 95.95 mm - CRF450R P5F0960320006A
ATHENA
MSRP: $261.07Now: $235.00Was: $261.07When your CRF450R's piston shows wear, combustion efficiency drops and power delivery suffers—this ATHENA piston kit restores that performance with precision-engineered components built to OEM...09031746- SKU:
- 09031746
- Availability:
- Ships Same Business Day
- Weight:
- 1.53 LBS
- BORE SIZE METRIC:
- 95.95 MM
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- MODEL:
- A
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 450 CC
- TYPE:
- TOP END
MSRP: $261.07Now: $235.00Was: $261.07 -
On Sale
ATHENA Piston Kit with Gaskets - 95.96 mm - CRF450R P5F0960320006B
ATHENA
MSRP: $261.07Now: $235.00Was: $261.07A worn or damaged piston directly compromises combustion efficiency, power output, and engine longevity—especially in high-demand off-road riding. The ATHENA 95.96 mm Piston Kit restores your CRF450R...09031747- SKU:
- 09031747
- Availability:
- Ships Same Business Day
- Weight:
- 1.50 LBS
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- PISTON MATERIAL:
- FORGED
- BORE SIZE METRIC:
- 95.96 MM
- DISPLACEMENT:
- 450 CC
- MODEL:
- B
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
MSRP: $261.07Now: $235.00Was: $261.07 -
On Sale
ATHENA Piston Kit with Gaskets - 95.97 mm - KX450F P5F0960068007A
ATHENA
MSRP: $265.02Now: $239.00Was: $265.02When you're pushing a KX450F to its limits, a worn or stock piston becomes your bottleneck—restricting flow, sapping power, and threatening reliability under sustained load. The ATHENA Piston Kit...09031752- SKU:
- 09031752
- Availability:
- Ships Same Business Day
- Weight:
- 1.50 LBS
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- A
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- DISPLACEMENT:
- 450 CC
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 95.97 MM
- TYPE:
- TOP END
MSRP: $265.02Now: $239.00Was: $265.02 -
On Sale
ATHENA Piston Kit with Gaskets - 95.98 mm - KX450F P5F0960068007B
ATHENA
MSRP: $289.95Now: $239.00Was: $289.95A worn or damaged piston directly kills your engine's compression, throttle response, and overall reliability—especially critical in high-demand 4-stroke off-road applications. The ATHENA Piston Kit...09031753- SKU:
- 09031753
- Availability:
- Ships Same Business Day
- Weight:
- 1.51 LBS
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 450 CC
- TYPE:
- TOP END
- MODEL:
- B
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 95.98 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
MSRP: $289.95Now: $239.00Was: $289.95 -
On Sale
ATHENA Piston Kit with Gaskets - 95.95 mm - KX450F P5F0960066002A
ATHENA
MSRP: $273.07Now: $246.00Was: $273.07When your KX450F is pushing peak RPMs on the track or trail, a worn piston compromises compression, power delivery, and engine longevity. The ATHENA Piston Kit delivers OE-equivalent reliability with...09031754- SKU:
- 09031754
- Availability:
- Ships Same Business Day
- Weight:
- 1.60 LBS
- COMPRESSION RATIO IMPERIAL:
- 12.5:1
- MODEL:
- A
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE SIZE METRIC:
- 95.95 MM
- PRODUCT NAME:
- PISTON KIT
- DISPLACEMENT:
- 450 CC
- TYPE:
- TOP END
MSRP: $273.07Now: $246.00Was: $273.07 -
On Sale
ATHENA Piston Kit with Gaskets - 94.95 mm - SXF450 P5F0950081002A
ATHENA
MSRP: $269.95Now: $252.00Was: $269.95When you're pushing your SXF450 to its limits, your piston needs to deliver reliability under extreme heat and pressure. The ATHENA Piston Kit combines OE-equivalent durability with enhanced material...09031756- SKU:
- 09031756
- Availability:
- Ships Same Business Day
- Weight:
- 1.54 LBS
- BORE SIZE METRIC:
- 94.95 MM
- TYPE:
- TOP END
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- MODEL:
- A
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- 12.8:1
- PISTON MATERIAL:
- FORGED
- DISPLACEMENT:
- 449 CC
- RIDING STYLE:
- OFF-ROAD
MSRP: $269.95Now: $252.00Was: $269.95
