ATV/UTV Engine
ATV/UTV Engine Parts at JJ Motorsports
Maximize your ATV or UTV's engine life with top-quality components from JJ Motorsports. Our selection includes gasket kits, connecting rods, water pump rebuild kits, and timing plugs designed for reliable sealing, strength, and easy installation in demanding off-road conditions. Compatible with Polaris, Can-Am, Honda, and more, these parts ensure peak power, reduced wear, and efficient operation for trail riding or utility work.
Shop trusted brands like Moose Racing for rebuild kits and Winderosa for gaskets. Explore related categories such as ATV/UTV air and fuel for intake upgrades or ATV/UTV drivetrain for transmission enhancements.
Top ATV/UTV Engine Products
- MOOSE UTILITY Clutch Cover Gasket Seal 500-1265-PU – Durable seal for clutch cover protection.
- WINDEROSA Standard Bore Gasket Kit 810585 – Complete kit for engine sealing and rebuilds.
- WORKS CONNECTION Engine Timing Plug 24-590 – Precision plug for accurate timing adjustments.
- MOOSE RACING Connecting Rod MR5026 – High-strength rod for engine durability.
- MOOSE RACING Water Pump Rebuild Kit 821865 – Comprehensive kit for water pump maintenance.
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
-
PROX Gasket Kit - Complete 34.3426
PROX
$214.95A complete gasket kit is essential for any engine rebuild or overhaul—it ensures a proper seal across all critical engine surfaces, preventing oil leaks, coolant seepage, and combustion blowby that compromise performance and reliability. The PROX Gasket...09347104- SKU:
- 09347104
- Availability:
- Ships Same Business Day
- Weight:
- 0.50 LBS
- RIDING STYLE:
- ATV
- ENGINE TYPE:
- 4-STROKE
- PRODUCT NAME:
- GASKET KIT
- TYPE:
- COMPLETE
- UNITS:
- KIT
$214.95 -
PROX Top End Gasket Set - Honda 35.1494
PROX
$88.95A proper top-end gasket set is non-negotiable for maintaining compression integrity and preventing oil weeping between cylinder head and block surfaces. PROX's Honda-specific 35.1494 set delivers factory-equivalent sealing performance with materials...09347113- SKU:
- 09347113
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- UNITS:
- SET
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET SET
$88.95 -
PROX Top End Gasket Kit - TRX450ER 35.1496
PROX
$109.95A failing top end gasket kit compromises combustion seal integrity, leading to power loss, oil seepage, and accelerated wear on critical engine components. The PROX Top End Gasket Kit for your TRX450ER delivers OEM-equivalent sealing performance with...09347114- SKU:
- 09347114
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- UNITS:
- KIT
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET KIT
- RIDING STYLE:
- ATV
$109.95 -
PROX Top End Gasket Set - Yamaha 35.2280
PROX
$41.95A worn or failing top-end gasket set is one of the fastest ways to lose compression, invite oil seepage, and compromise engine reliability—especially in high-performance or race-prepped builds. The PROX 35.2280 Top End Gasket Set delivers OEM-equivalent...09347125- SKU:
- 09347125
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- PRODUCT NAME:
- GASKET SET
- UNITS:
- SET
$41.95 -
PROX Top End Gasket Set - Yamaha 35.2358
PROX
$62.95A quality top-end gasket set is critical for maintaining compression and preventing oil seepage that can compromise engine performance and reliability. PROX gasket sets are precision-engineered to OEM specifications, ensuring a proper seal under...09347126- SKU:
- 09347126
- Availability:
- Ships Same Business Day
- Weight:
- 0.10 LBS
- UNITS:
- SET
- RIDING STYLE:
- OFF-ROAD
- PRODUCT NAME:
- GASKET SET
- TYPE:
- TOP END
$62.95Qty in Cart: 0Quantity:Price:$62.95Subtotal: -
PROX Top End Gasket Set - Kawasaki/Suzuki 35.3423
PROX
$57.95A quality top end gasket set is non-negotiable when you're rebuilding or refreshing your engine—it's your first line of defense against combustion leaks that rob you of power and reliability. PROX's 35.3423 set ensures precise sealing across all critical...09347137- SKU:
- 09347137
- Availability:
- Ships Same Business Day
- Weight:
- 0.20 LBS
- PRODUCT NAME:
- GASKET SET
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- UNITS:
- SET
$57.95Qty in Cart: 0Quantity:Price:$57.95Subtotal: -
PROX Top End Gasket Set - Kawasaki 35.4705
PROX
$114.95A properly sealed top end is fundamental to engine reliability and performance—any combustion leak compromises both horsepower and longevity. The PROX Top End Gasket Set delivers OEM-equivalent sealing with the precision fit required for consistent...09347141- SKU:
- 09347141
- Availability:
- Ships Same Business Day
- Weight:
- 0.16 LBS
- PRODUCT NAME:
- GASKET SET
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- RIDING STYLE:
- UTV
- UNITS:
- SET
$114.95 -
PROX Top End Gasket Set - Polaris 35.5494
PROX
$29.95A leaking or failing top end gasket set compromises engine sealing, leading to coolant loss, oil seepage, and potential overheating—all threats to engine longevity and reliability. The PROX 35.5494 Top End Gasket Set delivers OEM-equivalent sealing for...09347142- SKU:
- 09347142
- Availability:
- Ships Same Business Day
- Weight:
- 0.21 LBS
- PRODUCT NAME:
- GASKET SET
- RIDING STYLE:
- ATV
- TYPE:
- TOP END
- UNITS:
- SET
$29.95Qty in Cart: 0Quantity:Price:$29.95Subtotal: -
PROX Piston Kit 01.1496.A
PROX
$210.95Whether you're rebuilding after high-mileage wear or restoring a seized engine, piston failure isn't an option. The PROX Piston Kit 01.1496.A delivers OEM-equivalent reliability with the precision manufacturing that keeps your engine running strong. As a...09101191- SKU:
- 09101191
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- PISTON DIAMETER METRIC:
- 95.96 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
- BORE SIZE METRIC:
- 95.96 MM
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- ATV
- PISTON SIZE METRIC:
- STANDARD SIZE A
- PRODUCT NAME:
- PISTON KIT
$210.95 -
PROX Piston Kit 01.1496.B
PROX
$195.95When your engine demands reliability under extreme conditions, OEM-equivalent pistons are non-negotiable. The PROX Piston Kit 01.1496.B delivers factory-specification performance with Japanese manufacturing precision, ensuring consistent ring seal,...09101192- SKU:
- 09101192
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- PISTON DIAMETER METRIC:
- 95.97 MM
- PISTON SIZE METRIC:
- STANDARD SIZE B
- BORE SIZE METRIC:
- 95.97 MM
- PRODUCT NAME:
- PISTON KIT
$195.95 -
PROX Piston Kit 01.1496.C
PROX
$195.95When your engine demands reliability that matches factory specifications, the PROX Piston Kit 01.1496.C delivers the precision engineering required for consistent performance and longevity. This Japanese-manufactured replacement restores your engine to...09101193- SKU:
- 09101193
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- PISTON SIZE METRIC:
- STANDARD SIZE C
- BORE SIZE METRIC:
- 95.98 MM
- PISTON DIAMETER METRIC:
- 95.98 MM
- PRODUCT NAME:
- PISTON KIT
$195.95Qty in Cart: 0Quantity:Price:$195.95Subtotal: -
PROX Piston Kit 01.2436.B
PROX
$210.95A piston kit is the beating heart of your engine—when tolerances drift or ring blow-by creeps in, your power delivery suffers and fuel economy tanks. The PROX Piston Kit 01.2436.B delivers OEM-specification performance with the precision machining and...09101197- SKU:
- 09101197
- Availability:
- Ships Same Business Day
- Weight:
- 0.90 LBS
- BORE SIZE METRIC:
- 94.96 MM
- PISTON SIZE METRIC:
- STANDARD SIZE B
- ENGINE TYPE:
- 4-STROKE
- PISTON DIAMETER METRIC:
- 94.96 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$210.95Qty in Cart: 0Quantity:Price:$210.95Subtotal: -
PROX Piston Kit 01.2487.000
PROX
$121.95Worn or damaged pistons compromise combustion efficiency, power delivery, and engine longevity. The PROX Piston Kit 01.2487.000 restores your engine to OEM performance specifications with precision-manufactured components built to withstand demanding...09101198- SKU:
- 09101198
- Availability:
- Ships Same Business Day
- Weight:
- 0.98 LBS
- BORE SIZE METRIC:
- 83.00 MM
- PISTON DIAMETER METRIC:
- 83.00 MM
- PRODUCT NAME:
- PISTON KIT
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- STANDARD
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$121.95 -
PROX Piston Kit 01.2487.050
PROX
$121.95A piston kit is the foundation of reliable engine performance, and worn or damaged pistons directly compromise compression, power delivery, and engine longevity. The PROX Piston Kit 01.2487.050 delivers OEM-equivalent quality with precision manufacturing...09101199- SKU:
- 09101199
- Availability:
- Ships Same Business Day
- Weight:
- 1.00 LBS
- BORE SIZE METRIC:
- 83.50 MM
- PISTON DIAMETER METRIC:
- 83.50 MM
- PRODUCT NAME:
- PISTON KIT
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- +0.50 MM
$121.95 -
PROX Piston Kit 01.2706.A
PROX
$149.95A piston kit is one of the most critical internal engine components you'll rebuild or replace, and choosing the right one directly impacts engine reliability, efficiency, and longevity. The PROX Piston Kit 01.2706.A delivers OEM-equivalent performance...09101201- SKU:
- 09101201
- Availability:
- Ships Same Business Day
- Weight:
- 1.19 LBS
- PISTON SIZE METRIC:
- STANDARD SIZE A
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 101.94 MM
- RIDING STYLE:
- UTV
- ENGINE TYPE:
- 4-STROKE
- RIDING STYLE:
- ATV
- PISTON DIAMETER METRIC:
- 101.94 MM
- PISTON MATERIAL:
- ALUMINUM ALLOY
- UNITS:
- EACH
$149.95 -
PROX Piston Kit 01.2706.B
PROX
$149.95A piston kit is the foundation of engine reliability and performance—worn or damaged pistons directly compromise compression, power delivery, and engine longevity. The PROX Piston Kit 01.2706.B delivers OEM-equivalent quality with precision engineering,...09101202- SKU:
- 09101202
- Availability:
- Ships Same Business Day
- Weight:
- 1.20 LBS
- PRODUCT NAME:
- PISTON KIT
- RIDING STYLE:
- UTV
- PISTON DIAMETER METRIC:
- 101.95 MM
- PISTON SIZE METRIC:
- STANDARD SIZE B
- BORE SIZE METRIC:
- 101.95 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$149.95 -
PROX Piston Kit 01.2707.A
PROX
$149.95Piston failure doesn't just sideline your engine—it can destroy your entire build. The PROX Piston Kit 01.2707.A delivers OEM-spec reliability with precision manufacturing that keeps your combustion chamber sealed and your power delivery consistent, lap...09101204- SKU:
- 09101204
- Availability:
- Ships Same Business Day
- Weight:
- 1.24 LBS
- PISTON DIAMETER METRIC:
- 101.94 MM
- BORE SIZE METRIC:
- 101.94 MM
- RIDING STYLE:
- UTV
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- PISTON SIZE METRIC:
- STANDARD SIZE A
- PRODUCT NAME:
- HIGH COMPRESSION PISTON KIT
$149.95Qty in Cart: 0Quantity:Price:$149.95Subtotal: -
PROX Piston Kit 01.3420.A
PROX
$205.95A worn or damaged piston directly compromises engine efficiency, compression, and reliability—making a quality replacement essential for maintaining peak performance. The PROX Piston Kit 01.3420.A delivers OEM-equivalent specifications with precision...09101206- SKU:
- 09101206
- Availability:
- Ships Same Business Day
- Weight:
- 0.86 LBS
- BORE SIZE METRIC:
- 89.96 MM
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- PISTON SIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON KIT
- UNITS:
- EACH
- PISTON DIAMETER METRIC:
- 89.96 MM
- RIDING STYLE:
- ATV
- RIDING STYLE:
- OFF-ROAD
$205.95 -
PROX Piston Kit 01.3420.C
PROX
$205.95Pistons are the hardworking heart of any engine, converting combustion energy into power. When OEM pistons wear or fail, you need a direct replacement that matches factory specifications without compromise. The PROX Piston Kit 01.3420.C delivers...09101208- SKU:
- 09101208
- Availability:
- Ships Same Business Day
- Weight:
- 0.86 LBS
- PISTON DIAMETER METRIC:
- 89.98 MM
- PRODUCT NAME:
- PISTON KIT
- BORE SIZE METRIC:
- 89.98 MM
- PISTON SIZE METRIC:
- STANDARD SIZE C
- RIDING STYLE:
- OFF-ROAD
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
$205.95 -
PROX Piston Kit 01.2435.A
PROX
$210.95A piston kit is one of the most critical components in your engine's combustion cycle, and worn or damaged pistons directly compromise compression, power output, and reliability. The PROX Piston Kit 01.2435.A delivers OEM-equivalent performance with...09100603- SKU:
- 09100603
- Availability:
- Ships Same Business Day
- Weight:
- 0.92 LBS
- ENGINE TYPE:
- 4-STROKE
- PISTON MATERIAL:
- ALUMINUM ALLOY
- RIDING STYLE:
- ATV
- UNITS:
- EACH
- BORE SIZE METRIC:
- 94.95 MM
- PISTON DIAMETER METRIC:
- 94.95 MM
- PISTON SIZE METRIC:
- STANDARD
- PRODUCT NAME:
- PISTON KIT
$210.95
