Engine Rotating Assemblies & Rebuild Kits

Hot Rods Complete Bottom End Rebuild Kits

When it's time to do a rebuild, Hot Rods complete bottom end rebuild kits are less expensive and longer lasting than OEM. These kits have all that you need to get back on track and are easy to put together. Each kit contains a crankshaft, main bearing/seals, and a complete gasket set. Water pump seals are not included. Great performance parts from Hot Rods will have you going, going, strong!

5.0 out of 5 stars ( 2 )

$225.21

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$1,940.51

Cylinder Works Big Bore Cylinder Kits

Eliminate the wait with Cylinder Works big bore cylinder kits. They arrive ready to install, eliminating the hassle of sending out your cylinder for re-plating or boring, and they're competitively priced compared to typical re-plating costs. These Cylinder Works cylinders look virtually identical to your OEM parts and are conveniently available in "stealthy" big bore sizes. Cylinder Works big bore cylinder kits come in a variety of sizes, so choose the one that best fits your application. Features include: * Super-convenient--just purchase and install * Nickel silicon carbide plated for long life * Honed to exact size for easy piston installation * Complete with gaskets, cylinder, and piston kit * No machine work required

Not Yet Reviewed

$503.69

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$999.95

S&S Cycle M8 131 in. Big Bore Kits

S&S Cycle 131 in. big bore kits are aimed at the Milwaukee Eight platform for 2017 and newer big twins—and open up a whole new level of performance for these engines. When paired with an S&S 4.625 in. stroker flywheel (sold separately), engine will be a true 131cubic inches. S&S builds their big bore kits and cranks to much tighter tolerances and with higher quality materials than the factory parts. If you're the proud owner of a Harley-Davidson® Milwaukee Eight big twin and have been waiting for just the thing to boost your M8's power—the wait is over! The S&S Cycle piston/cylinder kits will be a solid platform for massive power! Features and benefits: * Huge displacement increase means huge power increase * Bolt-on kit works with stock crankcases * 4 1/4 in. bore cylinders with a new 11:1 forged piston design * Original engine serial numbers are retained * Powdercoat finish match factory finish, giving the bike a "sleeper" advantage * Includes .045 in. multi-layered steel head gaskets * Retains stock engine height * Includes 131 in. Cam Cover Badge * Available with or without highlighted fins Note: This kit must be used with S&S Cycle stroker flywheels to achieve 131 in. displacement (P/N: 320-0605, 320-0620).

Not Yet Reviewed

$1,559.95

Cylinder Works Standard Bore Cylinder Kits

Eliminate the wait with Cylinder Works standard bore cylinder kits. They arrive ready to install, eliminating the hassle of sending out your cylinder for re-plating or boring, and they're competitively priced compared to typical re-plating costs. These cylinders look virtually identical to your OEM parts. Cylinder Works standard bore cylinder kits come in model-specific kits, so choose the one that best fits your application. Features include: * Super-convenient--just purchase and install * Nickel silicon carbide plated for long life * Honed to exact size for easy piston installation * Complete with gaskets, cylinder, and piston kit * No machine work required

4.67 out of 5 stars ( 3 )

$392.66

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$1,056.51

S&S Cycle M8 124 in. Big Bore Kits

Inspired by S&S Pro Stock drag race engines, S&S Cycle 124 in. big bore kits utilize a ductile cast iron liner wrapped in cast aluminum for optimum thermal conductivity and performance. These bolt-in kits do not require machining, re-balancing or engine removal, and include just about everything you'll need to complete the installation. S&S Cycle 124 in. big bore kits are available in wrinkle black or wrinkle black with highlighted finned cylinders. Transform your stock engine into a 124 in. monster with the installation of a 124 in. big bore kit from S&S Cycle! S&S Cycle 124 in. big bore kit features: * Available for 107 M8 models * 107 to 124 in. big bore kit * Bolt-on kit * Includes gaskets and hardware required for installation * 4.250 in. bore * Forged Pistons * 11:1 compression ratio

Not Yet Reviewed

$1,643.95

S&S Cycle 883 to 1200cc Hooligan Cylinder Kits

An 883 to 1200cc Hooligan cylinder kit for a Harley-Davidson®, like the ones made by S&S Cycle, provides a significant increase in engine displacement, resulting in substantially more power and torque without requiring major engine modifications, making it a popular upgrade for riders seeking better performance on their Sportster 883, with benefits like increased horsepower—by boosting the engine size from 883cc to 1200cc, the Hooligan kit delivers a noticeable power gain, allowing for better acceleration and highway cruising capabilities. Typically these kits are designed as "bolt-on" upgrades, meaning they can be installed without needing extensive machining or engine rebalancing, making the process relatively simple and straightforward. Compared to a complete engine rebuild, a Hooligan kit is a cost-effective way to significantly improve your bike's power. When installing a Hooligan kit, it may be necessary to upgrade the clutch to handle the increased torque produced by the larger engine. Depending on the specific kit and your bike setup, you may need to adjust fuel injection mapping to optimize performance.

Not Yet Reviewed

$1,128.95

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$1,822.95

S&S Cycle 4 in. Sidewinder Big Bore Kits

Inspired by S&S Pro Stock drag race engines, S&S Cycle 4 in. Sidewinder big bore kits utilize a ductile cast iron liner wrapped in cast aluminum for optimum thermal conductivity and performance. These bolt-in kits do not require machining, re-balancing, or engine removal, and include just about everything you'll need to complete the installation. S&S Cycle 4 in. Sidewinder kits offer the biggest cylinder bore that can be installed in a stock crankcase without machining! Features: * Low-friction ductile cast iron liner * 10.5:1 compression * Bolts in with no machining, balancing, or splitting the crankcases * 88 in. engines are boosted to 100 in. * 96 in. and 103 in. engines are boosted to 110 in. * Complete kits include cylinders, pistons, gaskets, and instructions * Wrinkle black and silver cylinders that match stock finish

Not Yet Reviewed

$1,540.95

S&S Cycle 1200cc to 1250cc Hooligan Cylinder Kits

Whether you are looking for better acceleration for everyday riding or more power for spirited driving, S&S Cycle 1200cc to 1250cc Hooligan cylinder kits provide a noticeable improvement. The larger displacement from 1200cc to 1250cc directly translates to more power, making the bike faster and more responsive, especially noticeable in acceleration and mid-range torque. These kits are designed to be "bolt-on" meaning they can be installed without needing to machine the engine cases or rebalance the crankshaft, making the upgrade process fairly straightforward. Each kit is tailored with the necessary components for your specific HD® model. Most Hooligan kits utilize the existing stock heads, pushrods, and fuel system, minimizing the need for additional parts or adjustments. Compared to a full engine rebuild or custom build, S&S Cycle's Hooligan kits are a relatively affordable way to significantly improve performance. Select the kit designed for your application needs.

Not Yet Reviewed

$1,822.95

Namura Technologies Top-End Repair Kits

Top-end rebuilds can help to improve the performance of your ride, and Namura Technologies top-end repair kits will keep your ATV, UTV, or off-road motorcycle running in peak condition! They include everything you need: pistons, top-end gasket kit, and wrist pin bearings (where applicable) in one convenient, time-saving package. Namura kits are available for a wide variety of makes and models, with specific bore and compression ratio parts to service your specific vehicle. Choose to do your rebuild with repair kits from Namura Technologies—the people who make pistons with attitude!

5.0 out of 5 stars ( 2 )

$37.50

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$286.99

Vertex Top-End Piston Kits

Vertex top-end piston kits are OEM-style replacements. These kits include everything needed to rebuild a top-end for the specific application selected. When applicable, the wrist pin bearing included is DLC-coated for added longevity. All piston skirts are coated with a high-tech molybdenum disulphide coating for faster break-in and increased piston life along with a T-5 hardening cycle. Rebuild your top-end without worries with Vertex top-end piston kits.

4.67 out of 5 stars ( 3 )

$113.36

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$544.46

Kibblewhite Cylinder Head Service Kits

Kibblewhite cylinder head service kits contain all items to completely refresh and upgrade cylinder heads for popular Dirt/MX and Side x Side models. These full kits feature KPMI's top-quality racing valvetrain components. Choose the kit packaged for your specific off-road machine. Features: * Save time money on your next cylinder head rebuild * One package, everything you need for factory recommended valvetrain service * Double your service life over OEM using KPMI valvetrain products * Kitted with value added savings Kits will include: * Retainers * Springs * Base washers (as required) * Seals * Guides * Intake and exhaust Black Diamond or White Diamond valves (Standard head size) * Complete Cometic top-end gasket kit

Not Yet Reviewed

$453.05

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$475.16

Summit Racing™ Pro LS 6.0L Rotating Assemblies

Summit Racing™ Pro LS 6.0L forged rotating assemblies provide industry-leading fit, finish, and durability at an affordable price. These kits are tested to over 1,200 hp in turbo applications. They're available in a wide range of fitment and performance options. Standard features and specs may include: * 4340 forged steel crank * Core hardened to optimum strength, tempered, and nitride hardened * Lightening rod journals, gun-drilled mains, and profiled counterweights for better engine acceleration * Maximum journal tolerances of +/- .0001 to ensure consistent bearing clearance * Straight-shot oiling for maximum oil film strength at the maximum load angle * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in. * 2618 forged aluminum pistons * Ultra-modern 2618 alloy forgings for boost and nitrous with maximum ring land thickness * Pressure-fed pin oiling with durable chromium steel wrist pins * Specially profiled and coated piston skirts for stroker applications with tight piston-to-wall clearance * Generous valve reliefs for extra piston-to-valve clearance accommodate cathedral and rectangle heads * Premium steel piston rings * Steel top rings designed for maximum life with boost and nitrous * File-fit rings for maximum ring seal, reduced friction, and tensions optimized for wet sump engines * Martensitic ductile Napier-hook second rings for strength and maximum oil control * Premium main and rod bearings * Clevite H-bearings are designed for high-rpm operation in racing applications * Tri-metal bearings designed with high bearing crush for maximum retention * Medium eccentricity shells with precision wall tolerance of +/- .00015 in.

5.0 out of 5 stars ( 8 )

$2,608.87

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$2,948.87

Summit Racing™ Pro LS Piston and Rod Kits

Summit Racing™ Pro LS piston and rod kits deliver industry-leading fit, finish, and durability at an affordable price. These assemblies are tested to over 1,200 hp in turbo applications. They're available in a broad range of fitment and performance options. Standard features and specs may include: * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual-ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in. * 2618 forged aluminum pistons * Ultra-modern 2618 alloy forgings for boost and nitrous with maximum ring land thickness * Pressure-fed pin oiling with durable chromium steel wrist pins * Specially profiled and coated piston skirts for stroker applications with tight piston-to-wall clearance * Generous valve reliefs for extra piston-to-valve clearance accommodate cathedral and rectangle heads * Precision wrist pins and retainers * Premium steel piston rings * Steel top rings designed for maximum life with boost and nitrous * File-fit rings for maximum ring seal, reduced friction, and tensions optimized for wet-sump engines * Martensitic ductile Napier-hook second rings for strength and maximum oil control

4.84 out of 5 stars ( 19 )

$1,485.97

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$1,662.97

Summit Racing™ Pro LS 5.7L Rotating Assemblies

Summit Racing™ Pro LS 5.7L forged rotating assemblies provide industry-leading fit, finish, and durability at an affordable price. These kits are tested to over 1,200 hp in turbo applications. They're available in a wide range of fitment and performance options. Standard features and specs may include: * 4340 forged steel crank * Core hardened to optimum strength, tempered, and nitride hardened * Lightening rod journals, gun-drilled mains, and profiled counterweights for better engine acceleration * Maximum journal tolerances of +/- .0001 to ensure consistent bearing clearance * Straight-shot oiling for maximum oil film strength at the maximum load angle * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in. * 2618 forged aluminum pistons * Ultra-modern 2618 alloy forgings for boost and nitrous with maximum ring land thickness * Pressure-fed pin oiling with durable chromium steel wrist pins * Specially profiled and coated piston skirts for stroker applications with tight piston-to-wall clearance * Generous valve reliefs for extra piston-to-valve clearance accommodate cathedral and rectangle heads * Premium steel piston rings * Steel top rings designed for maximum life with boost and nitrous * File-fit rings for maximum ring seal, reduced friction, and tensions optimized for wet sump engines * Martensitic ductile Napier-hook second rings for strength and maximum oil control * Premium main and rod bearings * Clevite H-bearings are designed for high-rpm operation in racing applications * Tri-metal bearings designed with high bearing crush for maximum retention * Medium eccentricity shells with precision wall tolerance of +/- .00015 in.

4.25 out of 5 stars ( 4 )

$2,610.87

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$2,950.87

Summit Racing™ Pro LS Crank and Rod Kits

Summit Racing™ Pro LS crank and rod kits deliver industry-leading fit, finish, and durability at an affordable price. These assemblies are tested to over 1,200 hp in turbo applications. Order the kit recommended for your vehicle and engine. Standard features and specs may include: * 4340 forged steel crank * Core hardened to optimum strength, tempered, and nitride hardened * Lightening rod journals, gun-drilled mains, and profiled counterweights for better engine acceleration * Maximum journal tolerances of +/- .0001 to ensure consistent bearing clearance * Straight-shot oiling for maximum oil film strength at the maximum load angle * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual-ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in.

4.0 out of 5 stars ( 1 )

$1,599.98

Summit Racing™ Pro LS 5.3L Rotating Assemblies

Summit Racing™ Pro LS 5.3L forged rotating assemblies provide industry-leading fit, finish, and durability at an affordable price. These kits are tested to over 1,200 hp in turbo applications. They're available in a wide range of fitment and performance options. Standard features and specs may include: * 4340 forged steel crank * Core hardened to optimum strength, tempered, and nitride hardened * Lightening rod journals, gun-drilled mains, and profiled counterweights for better engine acceleration * Maximum journal tolerances of +/- .0001 to ensure consistent bearing clearance * Straight-shot oiling for maximum oil film strength at the maximum load angle * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in. * 2618 forged aluminum pistons * Ultra-modern 2618 alloy forgings for boost and nitrous with maximum ring land thickness * Pressure-fed pin oiling with durable chromium steel wrist pins * Specially profiled and coated piston skirts for stroker applications with tight piston-to-wall clearance * Generous valve reliefs for extra piston-to-valve clearance accommodate cathedral and rectangle heads * Premium steel piston rings * Steel top rings designed for maximum life with boost and nitrous * File-fit rings for maximum ring seal, reduced friction, and tensions optimized for wet sump engines * Martensitic ductile Napier-hook second rings for strength and maximum oil control * Premium main and rod bearings * Clevite H-bearings are designed for high-rpm operation in racing applications * Tri-metal bearings designed with high bearing crush for maximum retention * Medium eccentricity shells with precision wall tolerance of +/- .00015 in.

Not Yet Reviewed

$2,608.87

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$2,948.87

Summit Racing™ Pro LS 6.2L Rotating Assemblies

Summit Racing™ Pro LS 6.2L forged rotating assemblies provide industry-leading fit, finish, and durability at an affordable price. These kits are tested to over 1,200 hp in turbo applications. They're available in a wide range of fitment and performance options. Standard features and specs may include: * 4340 forged steel crank * Core hardened to optimum strength, tempered, and nitride hardened * Lightening rod journals, gun-drilled mains, and profiled counterweights for better engine acceleration * Maximum journal tolerances of +/- .0001 to ensure consistent bearing clearance * Straight-shot oiling for maximum oil film strength at the maximum load angle * 4340 forged H-beam connecting rods * Designed for 5,000 ft./min. average piston speed in street and drag applications * 7/16 ARP 2000 rod bolts with 200,000 psi tensile strength; dual ribbed caps for maximum strength * Added stroker clearance and balanced to within +/- 1 gram per end * Full-floating and precision-honed in the USA to +/- .0001 in. * 2618 forged aluminum pistons * Ultra-modern 2618 alloy forgings for boost and nitrous with maximum ring land thickness * Pressure-fed pin oiling with durable chromium steel wrist pins * Specially profiled and coated piston skirts for stroker applications with tight piston-to-wall clearance * Generous valve reliefs for extra piston-to-valve clearance accommodate cathedral and rectangle heads * Premium steel piston rings * Steel top rings designed for maximum life with boost and nitrous * File-fit rings for maximum ring seal, reduced friction, and tensions optimized for wet sump engines * Martensitic ductile Napier-hook second rings for strength and maximum oil control * Premium main and rod bearings * Clevite H-bearings are designed for high-rpm operation in racing applications * Tri-metal bearings designed with high bearing crush for maximum retention * Medium eccentricity shells with precision wall tolerance of +/- .00015 in.

4.25 out of 5 stars ( 4 )

$2,589.87

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$2,956.87

Wiseco Powersports Garage Buddy Engine Rebuild Kits

Wiseco Powersports Garage Buddy engine rebuild kits are complete with components made from premium materials. They include a complete crankshaft assembly, OEM quality main bearings, all necessary gaskets, seals, o-rings, forged piston kit, and hour meter. The crankshafts feature double-forged connecting rods designed to provide the smoothest rotating assemblies possible. Having a complete bottom-end that's made of 100 percent forged material will give you peace of mind that your motor will last. Order the engine rebuild kit designed for your dirt bike, ATV, and UTV model.

Not Yet Reviewed

$989.99

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$1,009.99

Cylinder Works Power Valve Kits

If you have a broken power valve on your off-road machine, Cylinder Works power valve kits offer you quick and affordable access to OEM-quality replacements. Standard bore and a big bore version are available to provide long-lasting quality you can depend on. Regulate your exhaust port to reach optimal power and rev level ride after ride with Cylinder Works power valve kits.

1.0 out of 5 stars ( 1 )

$222.26

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$304.04