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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Hinson Racing Clutch Cover 2002-2016 Honda CRF450R C389
HINSON RACING
$159.99Factory clutch covers weren't engineered for sustained high-RPM racing environments—they overheat under load and compromise engagement consistency. The Hinson Racing Clutch Cover eliminates thermal buildup through strategic fin design and superior...09400818- SKU:
- 09400818
- Availability:
- Ships Same Business Day
- Weight:
- 0.76 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- MODEL:
- BILLETPROOF
$159.99 -
Hinson Racing Clutch Cover for Yamaha YZ450F 2010-2022 C416
HINSON RACING
$159.99The stock clutch cover on your YZ450F can't handle sustained high-RPM heat cycles without thermal degradation—especially in closed-course racing or extended trail sessions. Hinson's C416 clutch cover dissipates heat more effectively than OEM designs,...09400982- SKU:
- 09400982
- Availability:
- Ships Same Business Day
- Weight:
- 0.86 LBS
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- MODEL:
- BILLETPROOF
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
$159.99 -
Hinson Racing Clutch Cover Kawasaki KX85 2001-2025 C068
HINSON RACING
$159.99Thermal management is critical when you're pushing a KX85 to its limits on the track. The Hinson Racing Clutch Cover dissipates heat more effectively than stock covers, keeping your clutch engagement consistent lap after lap. Built with racing-grade...09401035- SKU:
- 09401035
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- MODEL:
- BILLETPROOF
$159.99 -
Hinson Racing Clutch Cover for Yamaha YFZ450 2004-2013 C196
HINSON RACING
$159.99Stock clutch covers aren't engineered for sustained high-RPM racing conditions—they'll overheat and cause engagement inconsistencies when you need reliability most. The Hinson Racing Clutch Cover replaces that weakness with superior thermal management...C196- SKU:
- C196
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- MODEL:
- BILLETPROOF
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
$159.99 -
Hinson Racing Clutch Cover for Suzuki RM250 2002-2008 C046
HINSON RACING
$159.99Heat buildup is the silent killer of clutch performance, especially during sustained high-RPM riding or racing conditions. The Hinson Racing Clutch Cover for your RM250 combats this with superior thermal management and materials that outperform stock...C046X- SKU:
- C046X
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- MODEL:
- BILLETPROOF
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- BLACK
- MATERIAL:
- T-6 ALUMINUM
- TYPE:
- CLUTCH
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
$159.99 -
Rekluse Clutch Cover KTM 65 SX 2024 RMS-0413065
REKLUSE
$229.00Stock clutch covers are vulnerable to trail damage and inadequate cooling under sustained riding. The Rekluse clutch cover upgrades your KTM 65 SX with billet aluminum construction and increased oil capacity, delivering better thermal management and...09401821- SKU:
- 09401821
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- COLOR/FINISH:
- ANODIZED
- MATERIAL:
- BILLET ALUMINUM
- PRODUCT NAME:
- COVER
- TYPE:
- CLUTCH
- COLOR/FINISH:
- BLACK
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- RIDING STYLE:
- STREET
$229.00 -
Rekluse Clutch Cover Honda CRF450R 2017-2025 RMS-409
REKLUSE
$189.00The stock CRF450R clutch cover was never designed to handle extended trail riding or high-performance use—it limits oil capacity and leaves your engine running hotter than necessary. The Rekluse billet aluminum cover increases oil volume for superior...09401824- SKU:
- 09401824
- Availability:
- Ships Same Business Day
- Weight:
- 1.05 LBS
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- MATERIAL:
- BILLET ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
$189.00 -
Rekluse Clutch Cover Kawasaki KX450F 2016-2018 RMS-444
REKLUSE
$179.00The stock clutch cover on your KX450F limits oil capacity and leaves your drivetrain vulnerable to trail impacts. The Rekluse RMS-444 replaces that weakness with a billet aluminum design that holds more oil for superior cooling and lubrication, while its...09401829- SKU:
- 09401829
- Availability:
- Ships Same Business Day
- Weight:
- 0.96 LBS
- COLOR/FINISH:
- BLACK
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- TYPE:
- CLUTCH
- COLOR/FINISH:
- ANODIZED
- MATERIAL:
- BILLET ALUMINUM
- PRODUCT NAME:
- COVER
$179.00 -
REKLUSE Clutch Cover Kawasaki KX450 2021 RMS-445
REKLUSE
$229.00Off-road riding demands clutch protection that can handle repeated impacts without compromising lubrication or performance. The REKLUSE Clutch Cover for your KX450 delivers the durability you need with a robust billet aluminum construction and increased...09401830- SKU:
- 09401830
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- RIDING STYLE:
- STREET
- PRODUCT NAME:
- COVER
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- MATERIAL:
- BILLET ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
$229.00 -
Rekluse Clutch Cover for Suzuki RM-Z450 2008-2025 RMS-464
REKLUSE
$229.00Stock clutch covers are vulnerable to trail damage and limited oil capacity—a liability when you're pushing hard on technical terrain. The Rekluse RMS-464 replaces that weakness with a billet aluminum cover engineered to absorb impacts while maintaining...09401831- SKU:
- 09401831
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- TYPE:
- CLUTCH
- COLOR/FINISH:
- BLACK
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- COLOR/FINISH:
- ANODIZED
- MATERIAL:
- BILLET ALUMINUM
- PRODUCT NAME:
- COVER
$229.00 -
Rekluse Clutch Cover Yamaha YZ250 1999-2025 RMS-470
REKLUSE
$229.00The stock YZ250 clutch cover leaves your bike vulnerable to trail damage and thermal stress. Rekluse's billet aluminum replacement fortifies your engine case with impact-resistant protection while increasing oil capacity for better cooling during...09401833- SKU:
- 09401833
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- MATERIAL:
- BILLET ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
$229.00 -
Rekluse Clutch Cover Yamaha YZ450F 2010-2021 WR450F 2016-2021 YZ450FX 2016-2021 RMS-476
REKLUSE
$229.00If you're running a YZ450F, WR450F, or YZ450FX hard, your clutch cover needs to handle sustained heat, pressure, and trail abuse without compromising engine lubrication. The Rekluse clutch cover increases oil capacity beyond OEM specs, ensuring...09401836- SKU:
- 09401836
- Availability:
- Ships Same Business Day
- Weight:
- 0.95 LBS
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- BLACK
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- TYPE:
- CLUTCH
- COLOR/FINISH:
- ANODIZED
- MATERIAL:
- BILLET ALUMINUM
- PRODUCT NAME:
- COVER
$229.00 -
Rekluse Clutch Cover Kawasaki KX250 2021-2024 RMS-0404140
REKLUSE
$229.00The stock KX250 clutch cover is vulnerable to impact damage and thermal stress during aggressive riding. Rekluse's billet aluminum cover replaces the OEM unit with a reinforced design that withstands rock strikes and boot catches while delivering greater...09401998- SKU:
- 09401998
- Availability:
- Ships Same Business Day
- Weight:
- 0.81 LBS
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- MATERIAL:
- BILLET ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH
- PRODUCT NAME:
- COVER
- UNITS:
- EACH
$229.00 -
VERTEX Piston Kit - High Compression 24113A
VERTEX
$367.95If you're building an engine that demands reliability under extreme combustion pressures, the VERTEX Piston Kit 24113A delivers the metallurgical precision required for sustained high-RPM performance. The T-5 heat treatment and molybdenum disulfide skirt...09104119- SKU:
- 09104119
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
- UNITS:
- KIT
- DISPLACEMENT:
- 450 CC
- COMPRESSION RATIO IMPERIAL:
- 13.3:1
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 94.95 MM
- RIDING STYLE:
- STREET
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- CYLINDER DIAMETER METRIC:
- 95.00 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
$367.95 -
VERTEX Piston Kit - High Compression 24113B
VERTEX
$367.95High-compression pistons demand precision engineering to handle extreme combustion pressures and thermal cycling without compromising durability or ring sealing. The VERTEX 24113B kit delivers race-proven construction with advanced surface treatments...09104120- SKU:
- 09104120
- Availability:
- Ships Same Business Day
- Weight:
- 0.60 LBS
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- FORGED HIGH COMPRESSION
- UNITS:
- KIT
- DISPLACEMENT:
- 450 CC
- COMPRESSION RATIO IMPERIAL:
- 13.3:1
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- STREET
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- CYLINDER DIAMETER METRIC:
- 95.00 MM
- PISTON DIAMETER METRIC:
- 94.96 MM
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- PRODUCT NAME:
- PISTON KIT
$367.95 -
VERTEX Piston Kit 22224B
VERTEX
$148.95A quality piston kit is the foundation of any high-performing engine—it directly impacts combustion efficiency, horsepower delivery, and long-term reliability. The VERTEX Piston Kit 22224B combines precision engineering with proven durability features,...09102116- SKU:
- 09102116
- Availability:
- Ships Same Business Day
- Weight:
- 0.47 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
- STYLE:
- CAST REPLICA
- DISPLACEMENT:
- 125 CC
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 54.00 MM
- PISTON DIAMETER METRIC:
- 53.94 MM
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- KIT
$148.95 -
VERTEX Piston Kit 22896B
VERTEX
$302.95Whether you're rebuilding a worn top end or upgrading to forged internals for higher compression and power, the VERTEX Piston Kit 22896B delivers the durability and precision demanded by serious racers and engine builders. Each piston is engineered with...09102120- SKU:
- 09102120
- Availability:
- Ships Same Business Day
- Weight:
- 1.09 LBS
- DISPLACEMENT:
- 450 CC
- PISTON DIAMETER METRIC:
- 94.94 MM
- STYLE:
- FORGED HIGH COMPRESSION
- UNITS:
- KIT
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- OFF-ROAD
- COMPRESSION RATIO IMPERIAL:
- 13.5:1
- CYLINDER DIAMETER METRIC:
- 95.00 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- FORGED 2618 ALUMINUM
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$302.95 -
VERTEX Piston Kit 23614B
VERTEX
$197.95The VERTEX Piston Kit 23614B delivers the durability and precision required for serious engine rebuilds and high-performance builds. Whether you're running cast or forged variants, each piston is engineered with advanced heat treatment and surface...09104646- SKU:
- 09104646
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- CYLINDER DIAMETER METRIC:
- 52.50 MM
- DISPLACEMENT:
- 99 CC
- PISTON MATERIAL:
- CAST
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- UNITS:
- KIT
- PISTON DIAMETER METRIC:
- 52.45 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$197.95 -
VERTEX Piston Kit 23614C
VERTEX
$170.95A piston kit is the foundation of reliable top-end performance, directly affecting power delivery, engine longevity, and overall durability. The VERTEX Piston Kit 23614C delivers precision-engineered components built to withstand extreme operating...09104647- SKU:
- 09104647
- Availability:
- Ships Same Business Day
- Weight:
- 0.30 LBS
- PISTON DIAMETER METRIC:
- 52.46 MM
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- DISPLACEMENT:
- 99 CC
- PISTON MATERIAL:
- CAST
- RIDING STYLE:
- OFF-ROAD
- STYLE:
- CAST REPLICA
- UNITS:
- KIT
- ENGINE TYPE:
- 2-STROKE
- PRODUCT NAME:
- PISTON KIT
- CYLINDER DIAMETER METRIC:
- 52.50 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$170.95 -
VERTEX Piston Kit with Gaskets VTK23614A
VERTEX
$223.95Whether you're rebuilding a high-mileage engine or upgrading to increased displacement, the VERTEX Piston Kit VTK23614A delivers the durability and performance you need for reliable power delivery. Built with forged 2618 aluminum and precision-engineered...09104648- SKU:
- 09104648
- Availability:
- Ships Same Business Day
- Weight:
- 0.85 LBS
- DISPLACEMENT:
- 100 CC
- PISTON DIAMETER METRIC:
- 52.44 MM
- COMPRESSION RATIO IMPERIAL:
- STANDARD
- PISTON MATERIAL:
- CAST
- PRODUCT NAME:
- TOP END PISTON KIT
- STYLE:
- CAST REPLICA
- UNITS:
- KIT
- CYLINDER DIAMETER METRIC:
- 52.50 MM
- ENGINE TYPE:
- 2-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- OFF-ROAD
- SKIRT COATING:
- MOLYBDENUM DISULPHITE
$223.95
