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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MOOSE RACING Valve Seal Kit M60-60340
MOOSE RACING
$15.95Valve seal degradation is one of the most common causes of oil leakage, compression loss, and increased blowby in high-performance engines. The MOOSE RACING Valve Seal Kit M60-60340 replaces worn OEM seals with precision-engineered components that...09262825- SKU:
- 09262825
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- SEAL KIT
- TYPE:
- VALVE STEM
- UNITS:
- KIT
- BASE COLOR:
- RED
- MATERIAL:
- VITON
- RIDING STYLE:
- OFF-ROAD
- APPLICATION:
- INTAKE
- COLOR/FINISH:
- RED
$15.95 -
MOOSE RACING Valve Shim - 8.90 x 2.08 - 5 pack MSE5PK890208
MOOSE RACING
$10.95Maintaining precise valve clearances is non-negotiable for engine longevity and performance—and having a complete shim kit on hand eliminates guesswork during valve adjustments. These forged 4140 shims deliver the durability and accuracy that...09261914- SKU:
- 09261914
- Availability:
- Ships Same Business Day
- Weight:
- 0.02 LBS
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- WATERCRAFT
- TYPE:
- VALVE
- VALVE SHIM THICKNESS METRIC:
- 2.08 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
- MATERIAL:
- ROLLED
- OUTSIDE DIAMETER METRIC:
- 8.90 MM
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- SNOW
- UNITS:
- 5 PACK
$10.95 -
MOOSE RACING Clutch Cylinder Guard - 400-525 13-092
MOOSE RACING
$27.95Hydraulic clutch cylinders are vulnerable to chain slap and impact damage on aggressive riding—unplanned downtime derails race day. The MOOSE RACING Clutch Cylinder Guard protects this critical component with CNC-machined aluminum construction, while...09500150- SKU:
- 09500150
- Availability:
- Ships Same Business Day
- Weight:
- 0.22 LBS
- COLOR/FINISH:
- BLACK
- MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- CASE SAVER
- RIDING STYLE:
- STREET
- COLOR/FINISH:
- ANODIZED
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- TYPE:
- SLAVE CYLINDER
$27.95 -
MOOSE RACING Case Saver - CRF250R 01-163
MOOSE RACING
$23.95Engine case damage from crashes or debris can sideline your CRF250R and drain your wallet fast. This MOOSE RACING case saver replaces the vulnerable OEM plastic guards with CNC-machined 6061 aluminum that actually withstands impact, keeping your engine...09500015- SKU:
- 09500015
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- ALUMINUM
- PRODUCT NAME:
- CASE SAVER
- UNITS:
- EACH
- BASE COLOR:
- SILVER
- MATERIAL:
- 6061 ALUMINUM
- TYPE:
- ENGINE
$23.95 -
MOOSE RACING Case Saver - CRF450R 01-164
MOOSE RACING
$23.95Engine case damage can sideline your CRF450R mid-season and drain your wallet fast. The MOOSE RACING Case Saver replaces flimsy OEM plastic guards with precision-engineered aluminum protection that actually withstands crashes, rocks, and aggressive trail...09500017- SKU:
- 09500017
- Availability:
- Ships Same Business Day
- Weight:
- 0.13 LBS
- BASE COLOR:
- SILVER
- MATERIAL:
- 6061 ALUMINUM
- UNITS:
- EACH
- PRODUCT NAME:
- CASE SAVER
- TYPE:
- ENGINE
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- OFF-ROAD
$23.95 -
MOOSE RACING Case Saver - YZ250F 04-163
MOOSE RACING
$23.95Engine case damage can sideline your YZ250F and drain your wallet fast. The MOOSE RACING Case Saver replaces fragile OEM plastic guards with CNC-machined aluminum protection that actually looks purposeful on your bike. Whether you're racing or riding...09500019- SKU:
- 09500019
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- BASE COLOR:
- SILVER
- MATERIAL:
- 6061 ALUMINUM
- TYPE:
- ENGINE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- COLOR/FINISH:
- ALUMINUM
- PRODUCT NAME:
- CASE SAVER
$23.95 -
MOOSE RACING Case Saver - YZ450F 04-164
MOOSE RACING
$23.95Engine case damage on your YZ450F can mean expensive repairs and lost race time. This MOOSE RACING Case Saver replaces flimsy OEM plastic with rigid 6061 aluminum, delivering real protection where it matters most. Built and proven by riders who demand...09500021- SKU:
- 09500021
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- COLOR/FINISH:
- ALUMINUM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- BASE COLOR:
- SILVER
- MATERIAL:
- 6061 ALUMINUM
- PRODUCT NAME:
- CASE SAVER
- TYPE:
- ENGINE
$23.95 -
MOOSE RACING Case Saver Guard - RMZ450 CSG16
MOOSE RACING
$37.95Engine case damage during a crash or tip-over can mean thousands in rebuild costs and lost race time. The MOOSE RACING Case Saver Guard protects your RMZ450's vulnerable crankcase with a slim, lightweight design that doesn't compromise your bike's...09500379- SKU:
- 09500379
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- COLOR/FINISH:
- RED
- TYPE:
- CASE SAVER
- COLOR/FINISH:
- BLACK
- PRODUCT NAME:
- GUARD
- UNITS:
- EACH
- MATERIAL:
- NYLON
- RIDING STYLE:
- OFF-ROAD
$37.95 -
MOOSE RACING Clutch Guard - Cylinder - Sherco 13-9019
MOOSE RACING
$42.95Hydraulic clutch cylinders are vulnerable to chain strikes and debris during aggressive riding—damage here means catastrophic clutch failure mid-race. The MOOSE RACING Clutch Guard shields your cylinder with purpose-built protection while integrated...09500919- SKU:
- 09500919
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- COLOR/FINISH:
- ANODIZED
- COLOR/FINISH:
- BLACK
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- TYPE:
- SLAVE CYLINDER
- MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- CASE SAVER
$42.95 -
MOOSE RACING Clutch Cover Gasket 817253
MOOSE RACING
$7.49A leaking clutch cover gasket compromises engine sealing and can lead to oil loss and contamination—exactly what you don't need mid-race or during a rebuild. The MOOSE RACING 817253 clutch cover gasket delivers OEM-equivalent sealing performance at a...M817253- SKU:
- M817253
- Availability:
- Ships Same Business Day
- Weight:
- 0.04 LBS
- UNITS:
- EACH
- TYPE:
- CLUTCH COVER
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- OFF-ROAD
$7.49 -
MOOSE RACING Complete Motor Gasket Kit - KTM 50SX 808312
MOOSE RACING
$32.09A complete engine and transmission rebuild demands precision gaskets and seals that won't fail mid-season. The MOOSE RACING Complete Motor Gasket Kit delivers OEM-quality components at a fraction of the cost, giving you the confidence to push your KTM...09340140- SKU:
- 09340140
- Availability:
- Ships Same Business Day
- Weight:
- 0.09 LBS
- TYPE:
- ENGINE
- TYPE:
- COMPLETE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
$32.09 -
MOOSE RACING Complete Motor Gasket Kit - DR350 808584
MOOSE RACING
$93.43A complete engine and transmission rebuild demands precision-fit gaskets and seals that won't fail mid-season. This MOOSE RACING kit eliminates the guesswork of sourcing individual components, giving you every gasket, o-ring, and seal needed for a...09340142- SKU:
- 09340142
- Availability:
- Ships Same Business Day
- Weight:
- 0.25 LBS
- TYPE:
- ENGINE
- TYPE:
- COMPLETE
- UNITS:
- KIT
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$93.43 -
MOOSE RACING Complete Motor Gasket Kit - KX125 808425
MOOSE RACING
$80.32A complete engine and transmission rebuild demands precision gaskets and seals that won't fail under load—the MOOSE RACING Complete Motor Gasket Kit delivers OEM-quality components at a fraction of the cost. This comprehensive set eliminates multiple...M808425- SKU:
- M808425
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- TYPE:
- ENGINE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
- TYPE:
- COMPLETE
- RIDING STYLE:
- OFF-ROAD
$80.32 -
MOOSE RACING Complete Motor Gasket Kit - KX125 808429
MOOSE RACING
$87.56A complete engine and transmission rebuild demands precision gaskets and seals that won't compromise your motor's integrity. This Moose Racing kit delivers OEM-quality components at a fraction of the cost, giving you the confidence to rebuild without...M808429- SKU:
- M808429
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- COMPLETE
- TYPE:
- ENGINE
- PRODUCT NAME:
- GASKET
- UNITS:
- KIT
$87.56 -
MOOSE RACING Ignition Cover Gasket 816031
MOOSE RACING
$9.53A leaking ignition cover gasket compromises engine sealing and can lead to oil seepage that damages surrounding components. The MOOSE RACING Ignition Cover Gasket 816031 delivers OEM-quality sealing performance at a fraction of OEM pricing, making it an...09340579- SKU:
- 09340579
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- STREET
- TYPE:
- IGNITION COVER
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- UNITS:
- EACH
$9.53 -
MOOSE RACING Clutch Cover Gasket 816093
MOOSE RACING
$10.87A leaking clutch cover gasket compromises engine integrity and creates messy cleanup work. The MOOSE RACING Clutch Cover Gasket delivers OEM-equivalent sealing performance at a fraction of OEM pricing, using high-tech materials engineered for durability...09340580- SKU:
- 09340580
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- CLUTCH COVER
- PRODUCT NAME:
- GASKET
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$10.87 -
MOOSE RACING Ignition Cover Gasket 816211
MOOSE RACING
$8.55A leaking ignition cover gasket compromises engine sealing and can lead to oil loss and contamination. MOOSE RACING's OEM-equivalent replacement gasket delivers precision fitment and reliable sealing at a fraction of dealership pricing. Whether you're...09341006- SKU:
- 09341006
- Availability:
- Ships Same Business Day
- Weight:
- 0.09 LBS
- TYPE:
- IGNITION COVER
- PRODUCT NAME:
- GASKET
- UNITS:
- EACH
- RIDING STYLE:
- OFF-ROAD
$8.55 -
MOOSE RACING Countershaft Sprocket Seal Kit - KTM 25-4007
MOOSE RACING
$27.95Your countershaft seal is one of the hardest-working components in your drivetrain—and one of the easiest to overlook until it fails. The MOOSE RACING Countershaft Sprocket Seal Kit is engineered to prevent oil leakage, protect bearing surfaces, and...09350434- SKU:
- 09350434
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
- APPLICATION:
- COUNTERSHAFT
- PRODUCT NAME:
- SEAL KIT
$27.95 -
MOOSE RACING Countershaft Sprocket Seal Kit - Honda 25-4009
MOOSE RACING
$22.95Countershaft seals are critical wear components that prevent oil contamination and maintain proper lubrication in your transmission. A failed seal leads to fluid loss, metal-on-metal friction, and accelerated wear on expensive internal components. The...09350436- SKU:
- 09350436
- Availability:
- Ships Same Business Day
- Weight:
- 0.14 LBS
- APPLICATION:
- COUNTERSHAFT
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- SEAL KIT
- UNITS:
- KIT
$22.95 -
MOOSE RACING Countershaft Sprocket Seal Kit - Honda 25-4010
MOOSE RACING
$23.95Countershaft seals are critical wear items that prevent oil leakage and contamination in your transmission assembly. A failed seal compromises lubrication integrity and invites dirt into precision components, leading to premature wear or catastrophic...09350437- SKU:
- 09350437
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- APPLICATION:
- COUNTERSHAFT
- PRODUCT NAME:
- SEAL KIT
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- KIT
$23.95
