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
-
MOOSE RACING Complete Motor Gasket Kit - KX500 808470
MOOSE RACING
$64.22A complete engine and transmission rebuild demands precision gaskets that won't compromise performance or longevity. The MOOSE RACING Complete Motor Gasket Kit eliminates the guesswork by bundling...M808470- SKU:
- M808470
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- ENGINE
$64.22Qty in Cart: 0Quantity:Price:$64.22Subtotal: -
MOOSE RACING Top End Gasket Kit - XR650L 810281
MOOSE RACING
$70.25A top-end rebuild demands precision gaskets and seals that won't compromise engine integrity or cost you a fortune. The MOOSE RACING Top End Gasket Kit delivers OEM-quality components at a fraction...M810281- SKU:
- M810281
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$70.25 -
LA Sleeve Cylinder Sleeve for 2001 Kawasaki KX125 KA5451
LA SLEEVE
$131.95Cylinder wear is inevitable on high-mileage two-strokes, but a degraded bore doesn't mean engine replacement. The LA Sleeve Cylinder Sleeve KA5451 restores your KX125's original bore geometry and...KA5451- SKU:
- KA5451
- Availability:
- Ships Same Business Day
- Weight:
- 0.75 LBS
- BORE SIZE METRIC:
- 54.00 MM
- COLOR/FINISH:
- CHROME
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CYLINDER SLEEVE
- UNITS:
- EACH
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- TYPE:
- AC
$131.95Qty in Cart: 0Quantity:Price:$131.95Subtotal: -
LA Sleeve Cylinder Sleeve for Kawasaki KX250 2002-2003 66.40mm Bore KA5471
LA SLEEVE
$148.95When your KX250's cylinder wall begins to show signs of wear, a cylinder sleeve restores lost compression and ring sealing without a complete engine replacement. The LA SLEEVE KA5471 is...KA5471- SKU:
- KA5471
- Availability:
- Ships Same Business Day
- Weight:
- 1.42 LBS
- COLOR/FINISH:
- CHROME
- RIDING STYLE:
- OFF-ROAD
- BORE SIZE METRIC:
- 66.40 MM
- PRODUCT NAME:
- CYLINDER SLEEVE
- UNITS:
- EACH
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- TYPE:
- AC
$148.95Qty in Cart: 0Quantity:Price:$148.95Subtotal: -
LA Sleeve Cylinder Sleeve 66.40mm Bore Honda CR250R 2001 H5448
LA SLEEVE
$148.95A worn cylinder sleeve compromises compression, increases blowby, and degrades throttle response—exactly why a precision replacement matters on your CR250R. The LA SLEEVE H5448 restores factory bore...H5448- SKU:
- H5448
- Availability:
- Ships Same Business Day
- Weight:
- 1.45 LBS
- CYLINDER BORE COATING:
- CHROME-MOLY ALLOY
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- AC
- BORE SIZE METRIC:
- 66.40 MM
- COLOR/FINISH:
- CHROME
- PRODUCT NAME:
- CYLINDER SLEEVE
- UNITS:
- EACH
$148.95 -
On Sale
KIBBLEWHITE Valve Guide 40-40120
KIBBLEWHITE
MSRP: $17.70Now: $15.93Was: $17.70Valve guide wear compromises cylinder head sealing and increases oil consumption—a problem that compounds with high-performance engine builds and extended track sessions. The KIBBLEWHITE 40-40120...09260168- SKU:
- 09260168
- Availability:
- Ships Same Business Day
- Weight:
- 0.03 LBS
- UNITS:
- EACH
- APPLICATION:
- EXHAUST
- INSIDE DIAMETER IMPERIAL:
- 0.1760'
- SIZE IMPERIAL:
- STANDARD
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- C630 BRONZE
- OUTSIDE DIAMETER IMPERIAL:
- 0.3765'
- PRODUCT NAME:
- VALVE GUIDE
MSRP: $17.70Now: $15.93Was: $17.70 -
On Sale
KIBBLEWHITE Exhaust Valve 80-80217H
KIBBLEWHITE
MSRP: $37.55Now: $33.80Was: $37.55High-revving engines demand valve materials that can withstand extreme temperatures, pressure cycling, and combustion forces without degradation. KIBBLEWHITE's White Diamond™ exhaust valves are...09260110- SKU:
- 09260110
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- HEAD DIAMETER METRIC:
- 28.00 MM
- LENGTH IMPERIAL:
- 2.955'
- MATERIAL:
- STAINLESS STEEL
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- SIZE METRIC:
- STANDARD
- TULIP ANGLE:
- 20°
- UNITS:
- EACH
- APPLICATION:
- EXHAUST
- MODEL:
- WHITE DIAMOND™
- STEM DIAMETER IMPERIAL:
- 0.1956'
MSRP: $37.55Now: $33.80Was: $37.55 -
On Sale
KIBBLEWHITE Intake Valve - Honda 30-30220T
KIBBLEWHITE
MSRP: $92.51Now: $83.26Was: $92.51Kibblewhite's Tensilite® intake valves are engineered for engines that demand reliability under extreme conditions. Built from aerospace-grade titanium and finished with a CrN PVD coating, these...09262743- SKU:
- 09262743
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- TULIP ANGLE:
- 20°
- UNITS:
- EACH
- MODEL:
- TENSILITE®
- STEM DIAMETER IMPERIAL:
- 0.2158'
- HEAD DIAMETER METRIC:
- 36.00 MM
- PRODUCT NAME:
- VALVE
- MATERIAL:
- TITANIUM
MSRP: $92.51Now: $83.26Was: $92.51Qty in Cart: 0Quantity:Price:MSRP: $92.51Now: $83.26Was: $92.51Subtotal: -
On Sale
KIBBLEWHITE Intake Valve - Honda 30-31262T
KIBBLEWHITE
MSRP: $109.33Now: $98.40Was: $109.33Titanium intake valves are essential for high-RPM applications where stock valves can't handle sustained heat and load cycling. The KIBBLEWHITE Tensilite® valve delivers superior strength-to-weight...09262744- SKU:
- 09262744
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE
- RIDING STYLE:
- OFF-ROAD
- TULIP ANGLE:
- 20°
- UNITS:
- EACH
- MATERIAL:
- TITANIUM
- MODEL:
- TENSILITE®
- HEAD DIAMETER METRIC:
- 36.00 MM
- STEM DIAMETER IMPERIAL:
- 0.1960'
MSRP: $109.33Now: $98.40Was: $109.33Qty in Cart: 0Quantity:Price:MSRP: $109.33Now: $98.40Was: $109.33Subtotal: -
On Sale
KIBBLEWHITE Intake Valve - Suzuki 60-60512T
KIBBLEWHITE
MSRP: $109.33Now: $98.40Was: $109.33Intake valve performance directly impacts cylinder filling efficiency and combustion consistency—two factors that separate competitive engines from mediocre ones. The Kibblewhite Tensilite® valve...09262758- SKU:
- 09262758
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- TITANIUM
- APPLICATION:
- INTAKE
- PRODUCT NAME:
- VALVE
- UNITS:
- EACH
- MODEL:
- TENSILITE®
- TULIP ANGLE:
- 15°
- HEAD DIAMETER METRIC:
- 31.00 MM
- RIDING STYLE:
- OFF-ROAD
- STEM DIAMETER IMPERIAL:
- 0.1765'
MSRP: $109.33Now: $98.40Was: $109.33 -
Cylinder Works Big Bore Gasket Kit Honda CRF450R 2017-2018 11010-G01
CYLINDER WORKS
$70.65If you're running a big bore kit on your CRF450R, you need a gasket set engineered to handle the increased displacement and combustion pressures. The Cylinder Works Big Bore Gasket Kit ensures...09346004- SKU:
- 09346004
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- TYPE:
- CYLINDER
- BORE SIZE IMPERIAL:
- OVERSIZE (+3.00 MM)
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- DIAMETER METRIC:
- 99.00 MM
- PRODUCT NAME:
- GASKET KIT
$70.65Qty in Cart: 0Quantity:Price:$70.65Subtotal: -
Cylinder Works Standard Bore Cylinder for Kawasaki KX85 2006-2013 30009
CYLINDER WORKS
$543.95A worn or damaged cylinder directly compromises your KX85's power delivery and throttle response. The Cylinder Works Standard Bore Cylinder delivers OEM-spec performance without the downtime of...09310580- SKU:
- 09310580
- Availability:
- Ships Same Business Day
- Weight:
- 3.50 LBS
- OVERBORE METRIC:
- STANDARD
- STYLE:
- STANDARD
- COMPRESSION RATIO IMPERIAL:
- 10.0:1
- CYLINDER BORE COATING:
- NICKEL-SILICON CARBIDE
- DISPLACEMENT:
- 85 CC
- ENGINE TYPE:
- 2-CYCLE
- PRODUCT NAME:
- CYLINDER
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$543.95Qty in Cart: 0Quantity:Price:$543.95Subtotal: -
POWERSTANDS RACING Oil Cap Kit - Blue - M20 x 1.5 00-01310-25
POWERSTANDS RACING
$31.95If you're running a high-performance engine, your stock oil cap simply won't cut it. The POWERSTANDS Racing Oil Cap Kit replaces cheap plastic with precision-engineered aluminum that withstands...09500561- SKU:
- 09500561
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- COLOR/FINISH:
- ANODIZED
- PRODUCT NAME:
- CAP KIT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- COLOR/FINISH:
- BLUE
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
- TYPE:
- OIL FILLER
- DIAMETER - THREAD SIZE IMPERIAL:
- M20 X 1.5
$31.95Qty in Cart: 0Quantity:Price:$31.95Subtotal: -
POWERSTANDS RACING Oil Cap Kit - Blue - M20 x 2.5 00-01311-25
POWERSTANDS RACING
$31.95A quality oil cap isn't just a seal—it's a critical component that prevents contamination and fluid loss under extreme engine conditions. The POWERSTANDS Racing Oil Cap Kit delivers CNC-machined...09500563- SKU:
- 09500563
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- COLOR/FINISH:
- ANODIZED
- PRODUCT NAME:
- CAP KIT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- BLUE
- UNITS:
- KIT
- TYPE:
- OIL FILLER
- DIAMETER - THREAD SIZE IMPERIAL:
- M20 X 2.5
- MATERIAL:
- ALUMINUM
- RIDING STYLE:
- STREET
$31.95 -
SHINDY Needle Bearing - 18 mm x 23 mm x 24 mm 10-101
SHINDY
$10.95Piston pin needle bearings are critical wear components that directly impact engine reliability and performance consistency. A worn or degraded bearing increases friction, reduces power transfer...NB1452- SKU:
- NB1452
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- LENGTH:
- 24 MM
- LENGTH METRIC:
- 24 MM
- OUTSIDE DIAMETER METRIC:
- 23 MM
- APPLICATION:
- PISTON
- OUTSIDE DIAMETER:
- 23 MM
- RIDING STYLE:
- ATV
- TYPE:
- NEEDLE
- UNITS:
- EACH
- INSIDE DIAMETER:
- 18 MM
- INSIDE DIAMETER METRIC:
- 18 MM
- PRODUCT NAME:
- BEARING
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$10.95 -
On Sale
Wossner Piston Kit KTM 250 2005-2025 8169DC
WOSSNER
MSRP: $152.00Now: $144.40Was: $152.00When your 2-stroke KTM 250 is pushing hard on the track or trail, your piston kit needs to deliver consistent power while managing extreme temperatures and loads. The Wossner 8169DC is engineered to...09104863- SKU:
- 09104863
- Availability:
- Ships Same Business Day
- Weight:
- 0.80 LBS
- ENGINE TYPE:
- 2-STROKE
- PISTON SIZE METRIC:
- 66.36 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- BORE - OVERSIZE METRIC:
- +0.02 MM
- BORE SIZE METRIC:
- 66.42 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON MATERIAL:
- FORGED
- BORE - OVERSIZE:
- +0,02 MM
- DISPLACEMENT:
- 249 CC
- MODEL:
- STANDARD SERIES
- PRODUCT NAME:
- PISTON KIT
- TYPE:
- DUAL RING
MSRP: $152.00Now: $144.40Was: $152.00 -
MOOSE RACING Complete Motor Gasket Kit - YZ80 808612
MOOSE RACING
$36.47A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise performance or reliability. This MOOSE RACING kit delivers genuine OEM-quality replacement seals...M808612- SKU:
- M808612
- Availability:
- Ships Same Business Day
- Weight:
- 0.18 LBS
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
$36.47 -
MOOSE RACING Top End Gasket Kit - RM 250 810587
MOOSE RACING
$43.80A top-end rebuild demands precision gaskets and seals that won't compromise your engine's integrity or your budget. The MOOSE RACING Top End Gasket Kit delivers OEM-quality components at a fraction...M810587- SKU:
- M810587
- Availability:
- Ships Same Business Day
- Weight:
- 0.06 LBS
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- TOP END
- UNITS:
- KIT
$43.80Qty in Cart: 0Quantity:Price:$43.80Subtotal: -
MOOSE RACING Motor Seals - Arctic Cat/Suzuki 822239
MOOSE RACING
$48.21Engine seals are critical to maintaining oil pressure, preventing leaks, and ensuring reliable performance during both street and track applications. OEM seals often come at premium pricing when...09350822- SKU:
- 09350822
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- TYPE:
- OIL
- APPLICATION:
- ENGINE
- UNITS:
- SET
- PRODUCT NAME:
- SEAL
- RIDING STYLE:
- ATV
$48.21Qty in Cart: 0Quantity:Price:$48.21Subtotal: -
La Sleeve Sleeve and Piston Kit Honda TRX400FW Foreman 1995-2003 LAS-5286K
LA SLEEVE
$340.95If your Honda TRX400FW Foreman is showing signs of wear—loss of compression, declining power output, or rough idle—a top-end rebuild is the most cost-effective way to restore peak performance. The LA...09310357- SKU:
- 09310357
- Availability:
- Ships Same Business Day
- Weight:
- 4.15 LBS
- MATERIAL:
- IRON
- PRODUCT NAME:
- REBUILD KIT
- TYPE:
- CYLINDER
- UNITS:
- KIT
- RIDING STYLE:
- ATV
$340.95Qty in Cart: 0Quantity:Price:$340.95Subtotal:
