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!
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- Qty in Cart
- Quantity
- Price
- Subtotal
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COMETIC Exhaust Gasket EX456010S
COMETIC
$7.95Exhaust gasket failure is one of the quickest ways to compromise engine sealing and lose performance gains—especially under high heat and boost conditions. The COMETIC EX456010S delivers the thermal stability and structural integrity you need to keep...09344538- SKU:
- 09344538
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- SET
- BORE SIZE METRIC:
- 68.50 MM
- MODEL:
- HI-PERFORMANCE
- TYPE:
- EXHAUST
- PRODUCT NAME:
- GASKET
$7.95 -
COMETIC Exhaust Gasket - Yamaha EX641
COMETIC
$13.95Exhaust gasket failure is one of the most common causes of performance loss and costly engine damage. The COMETIC EX641 eliminates guesswork with precision engineering designed to handle extreme combustion temperatures while resisting blow-outs from...09344541- SKU:
- 09344541
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- BORE SIZE METRIC:
- 100.00 MM
- UNITS:
- SET
- RIDING STYLE:
- OFF-ROAD
- MODEL:
- HI-PERFORMANCE
- TYPE:
- EXHAUST
- PRODUCT NAME:
- GASKET
$13.95 -
COMETIC Exhaust Gasket EX657
COMETIC
$11.95Exhaust gasket failure leads to costly leaks, lost horsepower, and potential engine damage—especially under high-heat or high-boost conditions. The COMETIC EX657 is engineered to seal reliably across extreme temperature ranges, eliminating the risk of...09344545- SKU:
- 09344545
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- RIDING STYLE:
- ATV
- TYPE:
- EXHAUST
- MODEL:
- HI-PERFORMANCE
- PRODUCT NAME:
- GASKET
- BORE SIZE METRIC:
- 99.00 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- SET
$11.95 -
COMETIC Exhaust Gasket - Honda EX690064AM
COMETIC
$4.95Exhaust gasket failure leads to power loss, heat damage, and costly engine complications. The COMETIC EX690064AM delivers reliable, high-temperature sealing that won't fail under extreme conditions or aggressive tuning. Built with domestic precision and...09344546- SKU:
- 09344546
- Availability:
- Ships Same Business Day
- Weight:
- 0.11 LBS
- BORE SIZE METRIC:
- 39.00 MM
- RIDING STYLE:
- ATV
- MODEL:
- HI-PERFORMANCE
- PRODUCT NAME:
- GASKET
- THICKNESS METRIC:
- 1.63 MM
- TYPE:
- EXHAUST
- UNITS:
- SET
- RIDING STYLE:
- OFF-ROAD
- THICKNESS IMPERIAL:
- 0,064'
$4.95 -
COMETIC Exhaust Gasket EX817
COMETIC
$13.95Exhaust gasket failure means boost leaks, power loss, and costly engine damage—especially under high heat and pressure. The COMETIC EX817 is engineered for extreme conditions with a dual-layer construction that seals reliably across 4-stroke...09344554- SKU:
- 09344554
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- TYPE:
- EXHAUST
- UNITS:
- SET
- MODEL:
- HI-PERFORMANCE
- PRODUCT NAME:
- GASKET
- BORE SIZE METRIC:
- 90.00 MM
- RIDING STYLE:
- OFF-ROAD
- RIDING STYLE:
- UTV
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- RIDING STYLE:
- STREET
$13.95 -
COMETIC Valve Cover Gasket - Honda VC032010S
COMETIC
$39.95A failing valve cover gasket will bleed oil onto your engine bay and compromise your engine's cleanliness—exactly what you don't want during a race or on the street. The COMETIC VC032010S delivers OEM-quality sealing at a fraction of the cost, using...09344566- SKU:
- 09344566
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE COVER
- MODEL:
- HI-PERFORMANCE
- MATERIAL:
- ALUMINUM
- PRODUCT NAME:
- GASKET
- UNITS:
- EACH
$39.95 -
COMETIC Stator Gasket - Kawasaki EC1339032AFM
COMETIC
$16.95Stator cover gasket failures are costly downtime culprits—they weep, crawl, and demand tedious scraping during replacement. The COMETIC Stator Gasket eliminates these headaches with its AFM composite construction, delivering a reliable seal without...09344392- SKU:
- 09344392
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- MODEL:
- HI-PERFORMANCE
- PRODUCT NAME:
- GASKET
- TYPE:
- STATOR COVER
- RIDING STYLE:
- OFF-ROAD
- MATERIAL:
- AFM (ALUMINUM FOAM MATERIAL)
- UNITS:
- EACH
$16.95 -
Hot Cams Valve Shim 10.0 x 2.25 for 2008-2010 KTM 530 EXC-R 5PK1000225
HOT CAMS
$11.95Valve shim wear directly impacts your KTM 530 EXC-R's compression, valve timing, and overall engine responsiveness. This five-piece Hot Cams replacement pack gives you the precision shims needed to maintain tight tolerances and consistent performance...09261282- SKU:
- 09261282
- Availability:
- Ships Same Business Day
- Weight:
- 0.15 LBS
- OUTSIDE DIAMETER METRIC:
- 10.00 MM
- TYPE:
- VALVE
- PRODUCT NAME:
- SHIM
- UNITS:
- 5 PACK
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- VALVE SHIM THICKNESS METRIC:
- 2.25 MM
$11.95 -
Hot Cams Valve Shim Kit 7.48mm OD 1.20-3.50mm Honda CRF150R 2007-2022 HCSHIM01
HOT CAMS
$10.95Maintaining precise valve clearance is critical to keeping your CRF150R running at peak efficiency—and worn or mismatched shims will compromise both power delivery and engine longevity. The Hot Cams Valve Shim Kit gives you the exact OD and thickness...09261302- SKU:
- 09261302
- Availability:
- Ships Same Business Day
- Weight:
- 0.05 LBS
- MATERIAL:
- STEEL
- RIDING STYLE:
- OFF-ROAD
- OUTSIDE DIAMETER METRIC:
- 7.48 MM
- RIDING STYLE:
- ATV
- PRODUCT NAME:
- SHIM
- RIDING STYLE:
- UTV
- TYPE:
- VALVE
- RIDING STYLE:
- STREET
- UNITS:
- 5 PACK
- VALVE SHIM THICKNESS METRIC:
- 1.20 MM
$10.95 -
Hot Cams Stage 1 Intake Camshaft for Yamaha YZ250F 2001-2013 4012-1IN
HOT CAMS
$335.95If you're running a YZ250F and want measurable gains in low-end torque and throttle response, the Hot Cams Stage 1 Intake Camshaft is a bolt-on upgrade that delivers without requiring valve spring replacement. This cam's ITR technology sharpens your...YZ250S1AI- SKU:
- YZ250S1AI
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- UNITS:
- EACH
- APPLICATION:
- INTAKE
- INTAKE DURATION IMPERIAL:
- 249°
- INTAKE LIFT METRIC:
- 8.48 MM
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- CAMSHAFT
$335.95 -
Hot Cams Stage 1 Intake Camshaft for Yamaha WR 400 F 1998-2000 4002-1IN
HOT CAMS
$294.95If you're running a WR 400 F and want genuine low-end grunt without compromising reliability, the Hot Cams Stage 1 intake camshaft is the straightforward upgrade that delivers. This is a bolt-on cam that works with your stock valve springs, meaning you...YZ426S1AI- SKU:
- YZ426S1AI
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- PRODUCT NAME:
- CAMSHAFT
- INTAKE LIFT METRIC:
- 8.80 MM
- INTAKE DURATION IMPERIAL:
- 260°
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
$294.95 -
Hot Cams Stage 2 Camshaft for 2000-2007 Honda XR650R 1010-2
HOT CAMS
$391.95If you're running a 2000-2007 Honda XR650R and want measurable gains in peak horsepower and throttle response, the Hot Cams Stage 2 Camshaft is the most direct path to real performance. This is a drop-in upgrade engineered to work with your stock valve...XR650S2A- SKU:
- XR650S2A
- Availability:
- Ships Same Business Day
- Weight:
- 1.40 LBS
- APPLICATION:
- INTAKE
- EXHAUST LIFT METRIC:
- 9.50 MM
- INTAKE LIFT METRIC:
- 9.57 MM
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- INTAKE DURATION IMPERIAL:
- 265°
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- CAMSHAFT
- TYPE:
- STAGE 2
- EXHAUST DURATION IMPERIAL:
- 260°
$391.95 -
Hot Cams Exhaust Camshaft for Suzuki RM-Z450 2015-2017 2321-1E
HOT CAMS
$289.95If you're serious about extracting maximum performance from your RM-Z450, a quality exhaust camshaft is essential—it directly controls valve timing and lift, which determines how efficiently your engine breathes at every RPM. The Hot Cams 2321-1E is...09251195- SKU:
- 09251195
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- UNITS:
- EACH
- APPLICATION:
- EXHAUST
- EXHAUST DURATION IMPERIAL:
- 248.35°
- RIDING STYLE:
- OFF-ROAD
- EXHAUST LIFT METRIC:
- 9.70 MM
- TYPE:
- STAGE 1
- PRODUCT NAME:
- CAMSHAFT
$289.95 -
Hot Cams Exhaust Camshaft for Yamaha YZ250F 2017-2018 4327-2E
HOT CAMS
$289.95If you're serious about extracting maximum performance from your YZ250F, cam selection directly impacts how your engine delivers power across the entire RPM band. The HOT CAMS Exhaust Camshaft 4327-2E is engineered to optimize both low-end torque...09251200- SKU:
- 09251200
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- CAMSHAFT
- TYPE:
- STAGE 2
- EXHAUST LIFT METRIC:
- 9.02 MM
- UNITS:
- EACH
- EXHAUST DURATION IMPERIAL:
- 252.83°
- RIDING STYLE:
- OFF-ROAD
$289.95 -
Hot Cams Stage 2 Camshaft for 2010-2016 Honda CRF450R 1260-2
HOT CAMS
$448.95If you're running a stock CRF450R cam, you're leaving power on the table—especially in the mid-range and top-end where races are won. The Hot Cams Stage 2 addresses this directly with a tuned valve profile that prioritizes peak horsepower without...09250844- SKU:
- 09250844
- Availability:
- Ships Same Business Day
- Weight:
- 1.15 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- APPLICATION:
- EXHAUST
- PRODUCT NAME:
- CAMSHAFT
- TYPE:
- STAGE 2
- EXHAUST LIFT METRIC:
- 9.04 MM
- EXHAUST DURATION IMPERIAL:
- 265°
- INTAKE DURATION IMPERIAL:
- 254°
- INTAKE LIFT METRIC:
- 10.38 MM
$448.95 -
Hot Cams Cam Chain 2004-2016 Kawasaki KX250F HC92RH2010114
HOT CAMS
$54.95A cam chain failure can leave your KX250F sidelined at the track or trail. The HOT CAMS HC92RH2010114 replaces the weak link with a heat-treated silent chain engineered to exceed OEM durability standards, giving you the reliability to focus on...09250845- SKU:
- 09250845
- Availability:
- Ships Same Business Day
- Weight:
- 0.40 LBS
- BASE FINISH:
- RAW
- COLOR/FINISH:
- RAW
- RIDING STYLE:
- STREET
- UNITS:
- EACH
- MATERIAL:
- STEEL
- MODEL:
- SILENT
- RIDING STYLE:
- OFF-ROAD
- CHAIN SIZE:
- 92RH2010
- PRODUCT NAME:
- CHAIN
- TYPE:
- CAM
$54.95 -
Hot Cams Stage 2 Intake Camshaft for Suzuki DR-Z400E 2000-2008 2251-2IN
HOT CAMS
$289.95The stock camshaft in your DR-Z400E limits what your engine can truly deliver. The Hot Cams Stage 2 intake camshaft unlocks significant gains in peak horsepower and mid-to-top-end power, giving you the throttle response and acceleration you've been...09250693- SKU:
- 09250693
- Availability:
- Ships Same Business Day
- Weight:
- 0.97 LBS
- APPLICATION:
- INTAKE
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
- UNITS:
- EACH
- INTAKE LIFT METRIC:
- 9.07 MM
- PRODUCT NAME:
- CAMSHAFT
- INTAKE DURATION IMPERIAL:
- 238.5°
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
$289.95 -
Hot Cams Exhaust Camshaft for Suzuki DR-Z400E 2000-2008 2252-2E
HOT CAMS
$320.95If you're running a DR-Z400E and serious about extracting every bit of performance from your engine, a quality exhaust camshaft is non-negotiable. Hot Cams' 2252-2E delivers measurable gains in throttle response and power consistency across the RPM...09250694- SKU:
- 09250694
- Availability:
- Ships Same Business Day
- Weight:
- 1.14 LBS
- PRODUCT NAME:
- CAMSHAFT
- RIDING STYLE:
- OFF-ROAD
- EXHAUST LIFT METRIC:
- 9.07 MM
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- EXHAUST DURATION IMPERIAL:
- 238°
- APPLICATION:
- EXHAUST
- TYPE:
- STAGE 2
$320.95 -
Hot Cams 10mm Valve Shim Kit for KTM 1190 Adventure 2014-2016 HCSHIM31
HOT CAMS
$109.95Valve clearance directly impacts combustion efficiency, engine longevity, and power delivery—and the Hot Cams 10mm Valve Shim Kit gives you the precision adjustment needed to dial in your KTM 1190 Adventure's performance. Whether you're running increased...09250726- SKU:
- 09250726
- Availability:
- Ships Same Business Day
- Weight:
- 0.65 LBS
- PRODUCT NAME:
- SHIM KIT
- RIDING STYLE:
- ADVENTURE TOURING / DUAL-SPORT
- UNITS:
- 5 PACK
- DIAMETER METRIC:
- 10.00 MM
- RIDING STYLE:
- OFF-ROAD
- TYPE:
- VALVE
$109.95 -
Hot Cams Cam Chain for Honda CRF250R 2004-2009 and CRF250X 2004-2017 HC92RH2015104
HOT CAMS
$80.95A worn or failing cam chain compromises valve timing precision and can lead to catastrophic engine damage if it breaks. The HOT CAMS HC92RH2015104 delivers OEM-exceeding durability with heat-treated links that resist wear and maintain tight tolerances...09250761- SKU:
- 09250761
- Availability:
- Ships Same Business Day
- Weight:
- 0.55 LBS
- BASE FINISH:
- RAW
- CHAIN SIZE:
- 92RH2015
- MATERIAL:
- STEEL
- MODEL:
- SILENT
- RIDING STYLE:
- OFF-ROAD
- COLOR/FINISH:
- RAW
- UNITS:
- EACH
- PRODUCT NAME:
- CHAIN
- TYPE:
- CAM
$80.95
