Looking to give your Harley Davidson Fat Boy a power upgrade? Discover the top 7 Big Bore Kits tailored to boost your motorcycle's performance effortlessly. From easy bolt-in installation to a significant power increase, these kits offer a range of options to suit your customization needs. Whether you're aiming for more horsepower or torque, these kits have got you covered. Stay tuned to explore how these kits can take your riding experience to the next level.

Things to Note

• Bolt-on installation for easy upgrade without machining.
• Various bore size options available for customization.
• Includes cylinders, forged pistons, rings, and gaskets.
• Made in the USA for quality assurance.
• Enhanced power with compression ratio considerations.

S&S Cycle 4 Bolt in Sidewinder Big Bore Cylinder and Piston Kit

For riders seeking a simple upgrade without the need for thorough modifications, the S&S Cycle 4 Bolt in Sidewinder Big Bore Cylinder and Piston Kit offers a convenient bolt-in solution. This kit allows for engine size increases from 88in. to 100in., and from 96in. and 103in. to 110in., providing a significant boost in power.

The 10.5:1 compression ratio ensures street-friendly and reliable performance. With a cast ductile iron sleeve in cast aluminum construction, superior heat transfer is guaranteed. The complete kit includes cylinders, forged pistons, rings, and gaskets, making it an all-inclusive package for riders looking to enhance their motorcycle's performance.

Additionally, the option of a wrinkle black or silver powder coat finish adds a touch of customization to the upgrade.

Best For: Riders looking for a convenient bolt-in solution to increase engine size and power without extensive modifications.

Pros:

• Easy bolt-in installation without the need for machining or splitting crankcases
• Superior heat transfer due to cast ductile iron sleeve in cast aluminum construction
• Complete kit includes cylinders, forged pistons, rings, and gaskets for a comprehensive upgrade package

Cons:

• Limited to specific engine size increases
• Higher compression ratio may require tuning adjustments
• Limited color options for powder coat finish

S&,S Cycle 107&Prime, Wrinkle Black Big Bore Kit 910-0500

The S&S Cycle 107' Wrinkle Black Big Bore Kit 910-0500 is a high-performance upgrade suitable for motorcycle enthusiasts seeking enhanced power and durability without the need for extensive modifications.

This bolt-on kit features the largest bore at 3.937' for stock engines, with cylinders that resemble OEM shape and color through 11 fins. The kit includes centrifugal cast cylinder liners with a tensile strength of 40,000 psi and CP pistons known for exceptional wear and noise characteristics.

Installation is made easy as no machining is required for the case or piston boring, and the package comes complete with top and bottom cylinder gaskets.

With a weight of 19.5 pounds and dimensions of 16.5 x 13.5 x 11 inches, this S&S Cycle kit offers motorcycle riders a reliable performance boost.

Best For: Motorcycle enthusiasts looking for a high-performance upgrade that provides enhanced power and durability without requiring extensive modifications.

Pros:

• Largest bore for stock engines at 3.937'
• Easy bolt-on installation with no machining required
• CP pistons offer exceptional wear and noise characteristics

Cons:

• May be on the heavier side at 19.5 pounds
• Limited color options (Wrinkle Black only)
• Higher price point compared to standard bore kits

S And S Cycle M8 Models W/107 124 In124 Big Bore Kit M8 Blk 910-0681 New

Ideal for riders seeking enhanced performance and power, the S And S Cycle M8 Models W/107 124 In124 Big Bore Kit M8 Blk 910-0681 offers a significant upgrade for Harley Davidson motorcycles from 2017 to 2020.

This bolt-on kit, available for both 107 and 114 M8 models, comes in a wrinkle black finish with non-highlighted fins, giving it a sleek appearance. With a 4.250in. bore, forged pistons, and a 10.5:1 compression ratio, this kit provides a substantial boost in power without the need for machining.

Additionally, it includes gaskets and all necessary hardware for a hassle-free installation. Manufactured in the USA by S&S Cycle, this big bore kit is designed to deliver exceptional performance and reliability for riders looking to take their Harley Davidson to the next level.

Best For: Riders looking to enhance the performance and power of their Harley Davidson motorcycles from 2017 to 2020 without the need for machining.

Pros:

• Significant power upgrade with a 4.250in. bore and 10.5:1 compression ratio.
• Bolt-on kit for easy installation without machining required.
• Made in the USA for quality and reliability.

Cons:

• Limited compatibility with specific Harley Davidson models from 2017 to 2020.
• May not be street-legal in all areas due to increased power output.
• Higher price point compared to standard bore kits.

S&S Cycle 910-0642 Bolt-In Sidewinder 4in. Big Bore Kit – 100in. – Silver

With its bolt-in design and superior heat transfer capabilities, the S&S Cycle 910-0642 Bolt-In Sidewinder 4in. Big Bore Kit in silver offers motorcycle enthusiasts a convenient and efficient way to increase engine size without the need for machining.

This kit is specifically designed for 88in., 96in., and 103in. engines, increasing them to 100in. or 110in. The 10.5:1 compression ratio guarantees a streetable and responsive engine performance.

The complete kit includes cylinders, forged pistons, rings, and gaskets, providing everything needed for the upgrade. Weighing 26.9 pounds and measuring 19.5 x 9 x 8 inches, this kit is manufactured by S&S Cycle with the part number 910-0642.

Available in wrinkle black or silver finish, it has received positive customer feedback with a rating of 4.6 out of 5 stars.

Best For: Riders looking to increase engine size conveniently and efficiently without the need for machining.

Pros:

• Bolt-in design with no machining required
• Superior heat transfer with cast ductile iron sleeve
• Complete kit includes cylinders, forged pistons, rings, and gaskets

Cons:

• Limited color options (only available in wrinkle black or silver finish)
• Specific compatibility with 88in., 96in., and 103in. engines
• Warranty details may vary, requiring further information from the manufacturer.

S&S Cycle 910-0650 Bolt-In Sidewinder 4in. Big Bore Kit – 110in. – Silver

Featuring a bolt-in design and a cast ductile iron sleeve, the S&S Cycle 910-0650 Bolt-In Sidewinder 4in. Big Bore Kit – 110in. – Silver is the top choice for motorcycle enthusiasts seeking a simple installation process and superior heat transfer.

With this kit, engine size increases from 88in. to 100in. and from 96in. and 103in. to 110in., providing a significant power boost. The 10.5:1 compression ratio ensures peak performance.

The complete kit includes cylinders, forged pistons, rings, and gaskets, offering everything needed for the upgrade. Available in a wrinkle black or silver powder coat finish, this kit enhances both performance and aesthetics.

Designed for various Harley Davidson models, the S&S Cycle 910-0650 Bolt-In Sidewinder 4in. Big Bore Kit is a highly rated product among customers, providing a seamless enhancement to motorcycle power.

Best For: Motorcycle enthusiasts looking for a straightforward upgrade to increase power and performance in their Harley Davidson models.

Pros:

• Bolt-in design allows for easy installation without the need for machining.
• Superior heat transfer with a cast ductile iron sleeve in cast aluminum construction.
• Complete kit includes cylinders, forged pistons, rings, and gaskets for a comprehensive upgrade package.

Cons:

• Not compatible with S&S 79cc heads, limiting compatibility with certain setups.
• Limited color options available with only wrinkle black or silver powder coat finishes.
• Higher compression ratio of 10.5:1 may require adjustments for some users.

S&S Cycle 910-0182 3 1/2in. Bore Cylinder and Piston Kit – Wrinkle Black

For riders seeking enhanced performance and power output, the S&S Cycle 910-0182 3 1/2in. Bore Cylinder and Piston Kit in Wrinkle Black offers a reliable upgrade option. This kit includes S&S 3 1/2in. bore (80in.) cylinders and forged pistons, along with rings, wrist pins, head, and base gaskets.

The flat-topped cast pistons are suitable for stock or S&S Performance Replacement heads, boasting an 8.8:1 compression ratio. Additionally, the cylinders come in a choice of natural or wrinkle black powder coat finish.

With its quality components and design, this kit provides a solid foundation for enhancing your motorcycle's performance capabilities. Riders can expect improved power delivery and a boost in overall engine efficiency with the installation of this S&S Cycle big bore kit.

Best For: Riders looking to enhance their motorcycle's performance and power output with a reliable upgrade option.

Pros:

• Includes S&S 3 1/2in. bore cylinders and forged pistons for improved performance.
• Flat-topped cast pistons suitable for stock or S&S Performance Replacement heads.
• Choice of natural or wrinkle black powder coat finish for customization.

Cons:

• May require professional installation for optimal results.
• Higher compression ratio may necessitate additional modifications for some riders.
• Cost of the kit may be a consideration for budget-conscious individuals.

S And S Cycle 17-18 M8 Models Big Bore Cylinder Set Blk 910-0683 New

The S&S Cycle 17-18 M8 Models Big Bore Cylinder Set Blk 910-0683 is a top choice for motorcycle enthusiasts seeking a bolt-on kit to enhance performance without the need for machining.

This set boasts a 4.250in. bore size and features forged pistons with a 10.5:1 compression ratio, providing a significant power boost to compatible Harley Davidson models from 2017 to 2020.

Available for both 107 and 114 M8 models, this set comes in highlighted and non-highlighted versions, sporting a wrinkle black finish with non-highlighted fins.

Weighing 26.6 pounds, the product measures 18 x 14 x 11 inches and is made in the USA.

The S&S 910-0683 cylinder set offers a hassle-free upgrade to elevate your motorcycle's performance.

Best For: Motorcycle enthusiasts looking to increase performance on their compatible Harley Davidson models without the need for machining.

Pros:

• Bolt-on kit for easy installation
• Significant power boost with 10.5:1 compression ratio
• Made in the USA for quality assurance

Cons:

• Limited compatibility to specific Harley Davidson models from 2017 to 2020
• Heavier weight compared to stock components
• May require additional tuning for optimal performance

Factors to Consider When Choosing Fat Boy Big Bore Kit

When choosing a Fat Boy Big Bore Kit, you should consider factors like kit size options, the installation process, compression ratio, piston material quality, and heat transfer efficiency.

These elements play a pivotal role in enhancing your motorcycle's performance and ensuring a smooth upgrade process.

Make sure to assess each factor carefully to select the kit that best suits your needs and preferences.

Kit Size Options

Consider key aspects like your riding style, intended use, and budget when selecting the right size Fat Boy Big Bore kit for your motorcycle.

Fat Boy Big Bore kits come in various sizes, such as 100in., 110in., and even 124in., offering different levels of performance enhancement. The size of the kit directly impacts the increase in engine displacement, with larger kits delivering more substantial power gains.

It's crucial to choose a kit size that aligns with your performance goals while maintaining reliability. Larger bore sizes often result in higher compression ratios, influencing the engine's overall performance characteristics.

Before making a decision, evaluate how you ride your motorcycle, whether for daily commuting, long-distance touring, or aggressive riding. Also, take into account your budget constraints, as larger kits usually come with a higher price tag.

Installation Process

Selecting the appropriate Fat Boy Big Bore kit involves assessing factors like ease of setup, component inclusiveness, essential tools, compatibility, and user feedback.

When choosing a kit, take into account the level of simplicity during setup. Some kits may demand intricate procedures like machining or crankcase separation, while others offer a more straightforward bolt-on setup process.

It's crucial to select a kit that includes all required components such as cylinders, pistons, rings, and gaskets to ensure a thorough upgrade without missing parts. Additionally, check if any specialized tools are necessary for the setup and calculate any additional expenses or time needed for tool procurement or professional help.

Confirm the kit is compatible with your motorcycle model and engine size for a proper fit and top-notch performance.

Compression Ratio Consideration

Selecting the appropriate compression ratio is vital when evaluating Fat Boy Big Bore kits for motorcycles. The compression ratio, which compares the total cylinder volume at the bottom and top of the piston stroke, has a significant impact on engine performance.

Opting for a higher compression ratio often leads to improved engine efficiency and power output. However, it's important to note that lower compression ratios offer more flexibility with lower-octane fuels and reduce the likelihood of engine knocking.

When deciding on a compression ratio for your big bore kit, it's essential to strike a balance between performance, reliability, and fuel requirements. The chosen compression ratio will play a key role in determining the overall power and fuel efficiency of your motorcycle's engine.

Thus, consider your riding needs and fuel preferences carefully when selecting the compression ratio for your Fat Boy Big Bore kit.

Piston Material Quality

When evaluating Fat Boy Big Bore kits for motorcycles, prioritize the quality of the piston material to guarantee durability and peak performance. Opting for high-quality pistons, typically made from materials like forged aluminum, guarantees superior strength and heat resistance.

The use of forged pistons in big bore kits is prevalent due to their reliability and resistance to wear over time. The material composition of the piston plays a significant role in factors such as heat dissipation and expansion rates, impacting the overall performance of the engine.

Heat Transfer Efficiency

Enhancing heat transfer efficiency is essential when evaluating Fat Boy Big Bore kits for motorcycles, as it directly impacts engine performance and longevity.

Efficient heat transfer plays a critical role in preventing overheating and potential engine damage. When considering these kits, look for quality materials such as cast ductile iron sleeves, as they can notably enhance heat transfer capabilities.

Improved heat dissipation not only helps in preventing overheating but also contributes to better overall engine reliability and durability.

Pay close attention to the design and materials of the cylinders and pistons in the kit, as they've a direct impact on heat transfer efficiency.

Opting for components specifically designed for efficient heat transfer can lead to a more robust and reliable engine performance, ensuring that your motorcycle operates at its best for longer periods without encountering issues related to overheating or inadequate cooling.

Compatibility With Models

Consider the compatibility of the Fat Boy Big Bore Kit with your specific Harley Davidson Fat Boy model and year to guarantee a seamless upgrade process. Confirm that the kit is designed to fit your bike with a bolt-on installation, eliminating the need for machining or modifications.

It's important to verify if the kit includes all necessary components such as cylinders, pistons, rings, and gaskets for a complete upgrade package. Additionally, take into account the compression ratio of the kit to ensure it aligns with your desired performance level.

Some kits may require specific compatibility requirements, like additional tuning or modifications, for peak performance. By choosing a kit that's precisely matched to your Fat Boy model and year, you can make the upgrading process smoother and more efficient, resulting in a powerful boost to your motorcycle's performance.

Finishing Options Available

Exploring the finishing options available for Fat Boy Big Bore Kits can significantly impact the aesthetic appeal and durability of your motorcycle engine. When selecting a big bore kit, you'll come across finishes like wrinkle black, silver powder coat, natural, or painted options.

Each finish can influence the overall look and style of your bike while also providing varying levels of durability and resistance to heat and corrosion. Popular choices such as wrinkle black or powder coat are favored for their sleek and modern appearance.

It's crucial to not only the visual impact but also the maintenance requirements associated with the finish you select. By evaluating the finishing options carefully, you can ensure that your motorcycle engine not only performs well but also looks great for miles to come.

Make a choice that aligns with your style preferences and maintenance capabilities to enhance the overall appeal of your ride.

Warranty Information

When selecting a Fat Boy Big Bore Kit, understanding the warranty information becomes essential in ensuring the quality and coverage of your investment. Warranty details typically encompass coverage specifics, duration, and any exclusions.

It's pivotal to opt for warranties that safeguard against manufacturing defects and guarantee that the kit meets stringent quality standards. Be sure to check if the warranty mandates specific installation procedures or necessitates professional installation for validity.

Keep in mind that warranty terms might differ based on the manufacturer or seller, so comparing options before purchasing is advisable. By comprehending the warranty terms, you can acquire peace of mind and assurance regarding your investment in a big bore kit.

Make an informed decision by thoroughly evaluating and understanding the warranty information associated with the Fat Boy Big Bore Kit you intend to purchase.

Frequently Asked Questions

Can I Install the Big Bore Kit Myself or Do I Need a Professional?

You can install the big bore kit yourself, but it's important to take into account your mechanical skills and experience.

If you have prior knowledge working on motorcycles and feel confident, it's achievable with the right tools and instructions.

However, if you're uncertain or want to avoid any potential mistakes, it's best to consult a professional.

They can guarantee the installation is done correctly, minimizing any risks of damaging your motorcycle's engine.

Will a Big Bore Kit Void My Motorcycle's Warranty?

You might be surprised, but installing a big bore kit could actually void your motorcycle's warranty. It's important to check your warranty terms before making any modifications.

Manufacturers often have strict guidelines regarding aftermarket upgrades that could impact the original warranty coverage. To avoid any issues, it's best to consult with your dealer or manufacturer to clarify the implications of installing a big bore kit on your bike's warranty.

How Will a Big Bore Kit Affect My Motorcycle's Fuel Efficiency?

Adding a big bore kit to your motorcycle can impact fuel efficiency. By increasing the engine's displacement, more fuel is required to power the larger combustion.

This can lead to decreased fuel efficiency, particularly if you're heavy on the throttle.

It's crucial to weigh this trade-off when deciding to install a big bore kit, as the boost in power may result in decreased miles per gallon.

Are There Any Additional Parts Needed for Installation?

You'll need to check if there are any additional parts required for the installation process.

It's vital to make sure you have everything necessary before starting the installation of your big bore kit.

Missing parts could lead to delays or complications down the line.

Always double-check the requirements and have everything ready to make the installation process smoother.

Can a Big Bore Kit Be Installed on Any Motorcycle Model?

Yes, a big bore kit can typically be installed on most motorcycle models. However, it's important to verify compatibility with your specific bike before purchasing and installing one.

Some models may require additional modifications or parts to accommodate the increased engine size.

Always double-check with your manufacturer or a professional mechanic to confirm a proper fit and performance boost for your motorcycle.

Conclusion

So there you have it, the 7 best Fat Boy big bore kits to give your Harley Davidson a powerful upgrade.

Did you know that the S&S Cycle Bolt-In Sidewinder 4in. Big Bore Kit can increase your motorcycle's power output by up to 20%?

With easy installation and top-quality components, these kits are the perfect choice for riders looking to take their bike to the next level.