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 Top End Gasket Kit - KTM SX85 P400270600088
ATHENA
MSRP: $99.95Now: $90.00Was: $99.95Specifically 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, or race gas with a higher compression. Kits do not...09346189- SKU:
- 09346189
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
MSRP: $99.95Now: $90.00Was: $99.95 -
On Sale
ATHENA Complete Gasket Kit - YZF450 P400485900197
ATHENA
MSRP: $163.95Now: $148.00Was: $163.95Head 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 transparent coating guarantees a perfect seal even at...09346208- SKU:
- 09346208
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
MSRP: $163.95Now: $148.00Was: $163.95 -
On Sale
ATHENA Top End Gasket Kit - Honda P400210600319
ATHENA
MSRP: $67.95Now: $61.00Was: $67.95Specifically 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, or race gas with a higher compression. Kits do not...09346346- SKU:
- 09346346
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
MSRP: $67.95Now: $61.00Was: $67.95 -
On Sale
ATHENA Complete Gasket Kit - Honda P400210900319
ATHENA
MSRP: $198.95Now: $179.00Was: $198.95Head 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 transparent coating guarantees a perfect seal even at...09346347- SKU:
- 09346347
- Availability:
- Ships Same Business Day
- Weight:
- 0.56 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
MSRP: $198.95Now: $179.00Was: $198.95 -
On Sale
ATHENA Top End Gasket Kit - Yamaha P400485600199
ATHENA
MSRP: $31.95Now: $29.00Was: $31.95Specifically 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, or race gas with a higher compression. Kits do not...09346359- SKU:
- 09346359
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $31.95Now: $29.00Was: $31.95 -
On Sale
ATHENA Complete Gasket Kit - Yamaha P400485900199
ATHENA
MSRP: $98.95Now: $89.00Was: $98.95Head 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 transparent coating guarantees a perfect seal even at...09346360- SKU:
- 09346360
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- COMPLETE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $98.95Now: $89.00Was: $98.95 -
On Sale
ATHENA Top End Gasket Kit - Yamaha P400485600212
ATHENA
MSRP: $72.95Now: $66.00Was: $72.95Specifically 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, or race gas with a higher compression. Kits do not...09346361- SKU:
- 09346361
- Availability:
- Ships Same Business Day
- Weight:
- 0.26 LBS
- TYPE:
- TOP END
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
MSRP: $72.95Now: $66.00Was: $72.95 -
On Sale
ATHENA Complete Gasket Kit - Yamaha P400485900212
ATHENA
MSRP: $183.95Now: $166.00Was: $183.95Head 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 transparent coating guarantees a perfect seal even at...09346362- SKU:
- 09346362
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- UNITS:
- KIT
MSRP: $183.95Now: $166.00Was: $183.95 -
On Sale
ATHENA Race Gasket Kit - Honda R2106-319
ATHENA
MSRP: $70.95Now: $64.00Was: $70.95Specifically 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 premium-quality base gaskets of different thicknesses to...09346365- SKU:
- 09346365
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET KIT
- STYLE:
- RACE
MSRP: $70.95Now: $64.00Was: $70.95 -
On Sale
ATHENA Race Gasket Kit - Yamaha R4856-198
ATHENA
MSRP: $25.95Now: $23.00Was: $25.95Specifically 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 premium-quality base gaskets of different thicknesses to...09346369- SKU:
- 09346369
- Availability:
- Ships Same Business Day
- Weight:
- 0.51 LBS
- PRODUCT NAME:
- GASKET KIT
- STYLE:
- RACE
- TYPE:
- TOP END
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $25.95Now: $23.00Was: $25.95 -
On Sale
ATHENA Water Pump Gasket Kit - Yamaha P400485475012
ATHENA
MSRP: $39.95Now: $36.00Was: $39.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346375- SKU:
- 09346375
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
MSRP: $39.95Now: $36.00Was: $39.95 -
On Sale
ATHENA Water Pump Gasket Kit - Yamaha P400485475013
ATHENA
MSRP: $37.95Now: $34.00Was: $37.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346376- SKU:
- 09346376
- Availability:
- Ships Same Business Day
- Weight:
- 0.36 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET KIT
MSRP: $37.95Now: $34.00Was: $37.95 -
On Sale
ATHENA Water Pump Gasket Kit - Kawasaki P400250475016
ATHENA
MSRP: $69.95Now: $63.00Was: $69.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346378- SKU:
- 09346378
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- TYPE:
- WATER PUMP
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $69.95Now: $63.00Was: $69.95 -
On Sale
ATHENA Water Pump Gasket Kit - KTM/Husqvarna P400270475020
ATHENA
MSRP: $61.95Now: $56.00Was: $61.95Include water pump gasket, clutch cover gasket, water pump shaft oil seals and washers, Kit contents will vary slightly based on application, Kits do not contain replacement bearings09346381- SKU:
- 09346381
- Availability:
- Ships Same Business Day
- Weight:
- 0.41 LBS
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- WATER PUMP
- UNITS:
- KIT
MSRP: $61.95Now: $56.00Was: $61.95 -
On Sale
ATHENA Top End Gasket Kit - KTM P400270600092
ATHENA
MSRP: $73.95Now: $67.00Was: $73.95Specifically 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, or race gas with a higher compression. Kits do not...09346460- SKU:
- 09346460
- Availability:
- Ships Same Business Day
- Weight:
- 0.31 LBS
- TYPE:
- TOP END
- UNITS:
- KIT
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- GASKET KIT
MSRP: $73.95Now: $67.00Was: $73.95 -
On Sale
ATHENA Connecting Rod Kit P40321011
ATHENA
MSRP: $128.95Now: $116.00Was: $128.95High-quality, lightweight connecting rods, Made with similar materials to the OEM component to ensure the same performance, Superficial high-frequency treatment for higher resistance that reduces rotational and alternating stresses, Kits include...09230473- SKU:
- 09230473
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- DISPLACEMENT:
- 250 CC
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
MSRP: $128.95Now: $116.00Was: $128.95 -
On Sale
ATHENA Connecting Rod Kit P40321012
ATHENA
MSRP: $156.95Now: $141.00Was: $156.95High-quality, lightweight connecting rods, Made with similar materials to the OEM component to ensure the same performance, Superficial high-frequency treatment for higher resistance that reduces rotational and alternating stresses, Kits include...09230474- SKU:
- 09230474
- Availability:
- Ships Same Business Day
- Weight:
- 1.21 LBS
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 250 CC
MSRP: $156.95Now: $141.00Was: $156.95 -
On Sale
ATHENA Connecting Rod Kit P40321013
ATHENA
MSRP: $160.95Now: $145.00Was: $160.95High-quality, lightweight connecting rods, Made with similar materials to the OEM component to ensure the same performance, Superficial high-frequency treatment for higher resistance that reduces rotational and alternating stresses, Kits include...09230475- SKU:
- 09230475
- Availability:
- Ships Same Business Day
- Weight:
- 1.60 LBS
- DISPLACEMENT:
- 450 CC
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- CONNECTING ROD KIT
MSRP: $160.95Now: $145.00Was: $160.95 -
On Sale
ATHENA Connecting Rod Kit P40321033
ATHENA
MSRP: $115.95Now: $104.00Was: $115.95High-quality, lightweight connecting rods, Made with similar materials to the OEM component to ensure the same performance, Superficial high-frequency treatment for higher resistance that reduces rotational and alternating stresses, Kits include...09230479- SKU:
- 09230479
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 125 CC
MSRP: $115.95Now: $104.00Was: $115.95 -
On Sale
ATHENA Connecting Rod Kit P40321034
ATHENA
MSRP: $121.95Now: $110.00Was: $121.95High-quality, lightweight connecting rods, Made with similar materials to the OEM component to ensure the same performance, Superficial high-frequency treatment for higher resistance that reduces rotational and alternating stresses, Kits include...09230480- SKU:
- 09230480
- Availability:
- Ships Same Business Day
- Weight:
- 1.10 LBS
- PRODUCT NAME:
- CONNECTING ROD KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DISPLACEMENT:
- 250 CC
- RIDING STYLE:
- STREET
MSRP: $121.95Now: $110.00Was: $121.95
