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
-
On Sale
ATHENA Piston Kit S4F05400017C
ATHENA
MSRP: $130.95Now: $118.00Was: $130.95Two-stroke pistons are made from 4032 silicium, Four-stroke pistons are made from 2618 silicium - the same material used to produce Formula 1 pistons, Both include 3% copper in materials for better...09103893- SKU:
- 09103893
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- BORE SIZE METRIC:
- 53.97 MM
- DISPLACEMENT:
- 124 CC
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- C
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STOCK
- PISTON HEAD SHAPE:
- FLAT TOP
- UNITS:
- KIT
MSRP: $130.95Now: $118.00Was: $130.95 -
On Sale
ATHENA Piston Kit S4F06640018C
ATHENA
MSRP: $187.95Now: $169.00Was: $187.95Two-stroke pistons are made from 4032 silicium, Four-stroke pistons are made from 2618 silicium - the same material used to produce Formula 1 pistons, Both include 3% copper in materials for better...09103894- SKU:
- 09103894
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- DISPLACEMENT:
- 249 CC
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- BORE SIZE METRIC:
- 66.36 MM
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- STREET
- PISTON HEAD SHAPE:
- DOMED
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- C
- COMPRESSION RATIO IMPERIAL:
- STOCK
- UNITS:
- KIT
MSRP: $187.95Now: $169.00Was: $187.95 -
On Sale
ATHENA Piston Kit S4C04850003B
ATHENA
MSRP: $119.95Now: $108.00Was: $119.95Two-stroke pistons are made from 4032 silicium, Four-stroke pistons are made from 2618 silicium - the same material used to produce Formula 1 pistons, Both include 3% copper in materials for better...09104655- SKU:
- 09104655
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- 4032 ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 48.45 MM
- COMPRESSION RATIO IMPERIAL:
- STOCK
- PISTON HEAD SHAPE:
- DOMED
- UNITS:
- KIT
- DISPLACEMENT:
- 85 CC
- TYPE:
- B
- PRODUCT NAME:
- PISTON KIT
MSRP: $119.95Now: $108.00Was: $119.95Qty in Cart: 0Quantity:Price:MSRP: $119.95Now: $108.00Was: $119.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit P400250600015
ATHENA
MSRP: $36.95Now: $31.00Was: $36.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09340205- SKU:
- 09340205
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- MATERIAL:
- RUBBER
- UNITS:
- KIT
- TYPE:
- TOP END
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
MSRP: $36.95Now: $31.00Was: $36.95 -
On Sale
ATHENA Complete Gasket Kit - Suzuki P400510850035
ATHENA
MSRP: $78.95Now: $71.00Was: $78.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09340208- SKU:
- 09340208
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- ENGINE TYPE:
- 2-STROKE
MSRP: $78.95Now: $71.00Was: $78.95Qty in Cart: 0Quantity:Price:MSRP: $78.95Now: $71.00Was: $78.95Subtotal: -
On Sale
ATHENA Gasket Kit - WR250R/X - 83 mm P400485160017
ATHENA
MSRP: $92.95Now: $90.00Was: $92.95Kits include aluminum cylinder with nickel-carbide coating designed with larger water jackets, Forged piston with molybdenum coating, Special gasket kit, Easy-to-follow step-by-step installation...09341846- SKU:
- 09341846
- Availability:
- Ships Same Business Day
- Weight:
- 0.22 LBS
- BORE SIZE METRIC:
- 83.00 MM
- DISPLACEMENT:
- 290 CC
- TYPE:
- TOP END
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- BORE SIZE:
- 83,00 MM
MSRP: $92.95Now: $90.00Was: $92.95 -
On Sale
ATHENA Complete Gasket Kit - Husqvarna P400220850261
ATHENA
MSRP: $256.95Now: $231.00Was: $256.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09342788- SKU:
- 09342788
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- ENGINE TYPE:
- -
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET KIT
MSRP: $256.95Now: $231.00Was: $256.95Qty in Cart: 0Quantity:Price:MSRP: $256.95Now: $231.00Was: $256.95Subtotal: -
On Sale
ATHENA Complete Gasket Kit - KX250 P400250850021
ATHENA
MSRP: $105.95Now: $95.00Was: $105.95Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high spring-back and superior tensile strength, Revolutionary...09342790- SKU:
- 09342790
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
MSRP: $105.95Now: $95.00Was: $105.95Qty in Cart: 0Quantity:Price:MSRP: $105.95Now: $95.00Was: $105.95Subtotal: -
On Sale
ATHENA Complete Gasket Kit - KTM P400270850049
ATHENA
MSRP: $109.95Now: $94.00Was: $109.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09342791- SKU:
- 09342791
- Availability:
- Ships Same Business Day
- Weight:
- 0.17 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- ENGINE TYPE:
- -
- PRODUCT NAME:
- GASKET KIT
MSRP: $109.95Now: $94.00Was: $109.95Qty in Cart: 0Quantity:Price:MSRP: $109.95Now: $94.00Was: $109.95Subtotal: -
On Sale
ATHENA Complete Gasket Kit - KTM P400270850028
ATHENA
MSRP: $136.95Now: $117.00Was: $136.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09342792- SKU:
- 09342792
- Availability:
- Ships Same Business Day
- Weight:
- 0.37 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- RIDING STYLE:
- STREET
- ENGINE TYPE:
- -
- PRODUCT NAME:
- GASKET KIT
- UNITS:
- KIT
MSRP: $136.95Now: $117.00Was: $136.95 -
On Sale
ATHENA Race Gasket Kit - CRF250R R2106-245
ATHENA
MSRP: $55.95Now: $50.00Was: $55.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during mid-season, Kits include a top-of-the line MLSS head gasket and two or more...09342807- SKU:
- 09342807
- Availability:
- Ships Same Business Day
- Weight:
- 0.23 LBS
- MATERIAL:
- RUBBER
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- MATERIAL:
- STEEL
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET KIT
- STYLE:
- RACE
MSRP: $55.95Now: $50.00Was: $55.95 -
On Sale
ATHENA Complete Gasket Kit - KTM P400270900061
ATHENA
MSRP: $185.95Now: $159.00Was: $185.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09343011- SKU:
- 09343011
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- UNITS:
- KIT
- ENGINE TYPE:
- -
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- STREET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
MSRP: $185.95Now: $159.00Was: $185.95Qty in Cart: 0Quantity:Price:MSRP: $185.95Now: $159.00Was: $185.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Honda P400210600172
ATHENA
MSRP: $113.95Now: $103.00Was: $113.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09343023- SKU:
- 09343023
- Availability:
- Ships Same Business Day
- Weight:
- 0.35 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- UNITS:
- KIT
MSRP: $113.95Now: $103.00Was: $113.95Qty in Cart: 0Quantity:Price:MSRP: $113.95Now: $103.00Was: $113.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Honda P400210600198
ATHENA
MSRP: $78.95Now: $71.00Was: $78.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09343024- SKU:
- 09343024
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
MSRP: $78.95Now: $71.00Was: $78.95Qty in Cart: 0Quantity:Price:MSRP: $78.95Now: $71.00Was: $78.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Kawasaki P400250600029
ATHENA
MSRP: $119.95Now: $108.00Was: $119.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09343028- SKU:
- 09343028
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- MATERIAL:
- SILICONE
- UNITS:
- KIT
MSRP: $119.95Now: $108.00Was: $119.95Qty in Cart: 0Quantity:Price:MSRP: $119.95Now: $108.00Was: $119.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Yamaha P400485600156
ATHENA
MSRP: $131.95Now: $119.00Was: $131.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09343034- SKU:
- 09343034
- Availability:
- Ships Same Business Day
- Weight:
- 0.24 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- UNITS:
- KIT
MSRP: $131.95Now: $119.00Was: $131.95Qty in Cart: 0Quantity:Price:MSRP: $131.95Now: $119.00Was: $131.95Subtotal: -
On Sale
ATHENA Complete Gasket Kit - Yamaha P400485850078
ATHENA
MSRP: $164.95Now: $141.00Was: $164.95Superior-quality gasket sets from Athena, Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high springback and...09343045- SKU:
- 09343045
- Availability:
- Ships Same Business Day
- Weight:
- 0.49 LBS
- RIDING STYLE:
- ATV
- TYPE:
- COMPLETE
- ENGINE TYPE:
- -
- PRODUCT NAME:
- GASKET KIT
- UNITS:
- KIT
MSRP: $164.95Now: $141.00Was: $164.95 -
On Sale
ATHENA Complete Gasket Kit P400270160067
ATHENA
MSRP: $56.95Now: $51.00Was: $56.95Kits include aluminum cylinder with nickel-carbide coating designed with larger water jackets, Forged piston with molybdenum coating, Special gasket kit, Easy-to-follow step-by-step installation...09343157- SKU:
- 09343157
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- BORE SIZE:
- 82,00 MM
- BORE SIZE METRIC:
- 82.00 MM
- DISPLACEMENT:
- 276 CC
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
MSRP: $56.95Now: $51.00Was: $56.95Qty in Cart: 0Quantity:Price:MSRP: $56.95Now: $51.00Was: $56.95Subtotal: -
On Sale
ATHENA Top End Gasket Kit - Yamaha P400485600197
ATHENA
MSRP: $57.95Now: $52.00Was: $57.95Specifically designed for the pro, semi-pro and amateur rider who freshens up their engine prior to a race or during midseason. Gives the rider a choice of using standard gas with stock compression,...09346215- SKU:
- 09346215
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- TYPE:
- TOP END
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $57.95Now: $52.00Was: $57.95Qty in Cart: 0Quantity:Price:MSRP: $57.95Now: $52.00Was: $57.95Subtotal: -
On Sale
ATHENA Complete Gasket Kit - Honda P400210900320
ATHENA
MSRP: $209.95Now: $189.00Was: $209.95Head gaskets feature rubber-coated spring steel construction, Soft steel base gaskets are rubber coated, Steel core materials feature high spring-back and superior tensile strength, Revolutionary...09346349- SKU:
- 09346349
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
MSRP: $209.95Now: $189.00Was: $209.95
