Upgrading your chainsaw with a big bore kit can significantly boost engine performance and extend the life of your tool. These kits often include a cylinder, piston, gasket sets, and other essential components for enhancing power and efficiency. Below is a summary of the top big bore kits available for various popular chainsaw models, helping you find the right fit for your machine.
| Product | Compatibility | Bore Size | Included Parts |
|---|---|---|---|
| Adefol Nikasil 44.7mm Big Bore Kit | Stihl 026, MS260, 026PRO | 44.7mm | Cylinder piston, gasket, oil seals, needle bearing, spark plug, plug, decompression valve |
| Adefol 47mm Big Bore Cylinder Piston Kit | Stihl MS291, MS271 Series | 47mm | Cylinder & piston |
| Haishine 45mm Nikasil Cylinder Piston Kit | Husqvarna 353, 351, 350, 346XP, 340 | 45mm | Cylinder piston, decompression valve, fuel filter |
| Mtanlo 44.7mm Big Bore Cylinder Piston Kit | Stihl 026, MS260, 026PRO | 44.7mm | Cylinder piston, crankshaft, gaskets, oil seals, needle bearing, spark plug, decompression valve |
| Mtanlo 56mm Big Bore Cylinder Piston Gasket Kit | Stihl MS660, 066, MS640, MS650 | 56mm | Cylinder piston, gasket |
Adefol 44.7mm Nikasil Big Bore Kit for Stihl 026 MS260
This Adefol Nikasil 44.7mm big bore kit is designed for Stihl 026, MS260, and 026PRO chainsaws, offering a precise fit and effective performance upgrade. The Nikasil-plated cylinder enhances durability and heat resistance for extended engine life. The kit includes a cylinder piston, gasket set, oil seal set, needle bearing, spark plug, cylinder plug, and decompression valve, providing a comprehensive overhaul solution. The replacement part number for easy identification is 1121 020 1217. This complete kit supports easier installation and improved engine efficiency.
Adefol 47mm Big Bore Cylinder Piston Kit for Stihl MS291 MS271
This 47mm Adefol big bore piston kit fits Stihl MS291, MS271, and their “C” and Pro variants. It replaces OEM part numbers 1141 020 1206 and 1141 020 1201. Crafted for a precision fit, the chrome piston and cylinder ensure optimal performance, making it suitable for users seeking reliable engine upgrades. The kit focuses on essential components that enhance power and durability in one compact unit.
Haishine 45mm Nikasil Cylinder Piston Kit for Husqvarna Chainsaws
The Haishine 45mm big bore big bore kit for Husqvarna 353, 351, 350, 346XP, and 340 offers a close OEM match (OEM numbers 5372531-02, 503869871). It incorporates a Nikasil-coated cylinder for superior wear resistance and heat dissipation. Additionally, it includes a decompression valve and fuel filter, supporting enhanced fuel efficiency and reduced engine strain. This kit is tailored for users who want to maintain Husqvarna’s performance standards while gaining some power improvements.
Mtanlo 44.7mm Big Bore Kit with Crankshaft for Stihl MS260 026 PRO
The Mtanlo 44.7mm big bore cylinder piston kit includes extensive replacement parts for Stihl 026, MS260, MS260C, and 026PRO chainsaws. Beyond the cylinder piston, the package provides a crankshaft, oil seals, crank and cylinder gaskets, needle bearing, spark plug, decompression valve, and crank bearing. The replacement part number is 1121 020 1217. This comprehensive kit serves users looking for a more thorough engine rebuild option for enhanced power and reliability.
Mtanlo 56mm Nikasil Big Bore Cylinder Piston Kit for Stihl MS660
This 56mm big bore kit by Mtanlo is compatible with Stihl MS660, 066, MS640, MS650, and MAGNUM chainsaws. Known for its Nikasil coating, the cylinder offers exceptional hardness and corrosion resistance. It replaces OEM part #1122 020 1211 and provides a robust upgrade ideal for heavy-duty chainsaw models needing increased displacement and more robust performance. This kit is suited for those who want to enhance engine power significantly while maintaining durability.
Buying Guide for Big Bore Chainsaw Kits
Selecting the right big bore chainsaw kit involves several key factors to ensure optimal performance and compatibility with your chainsaw model.
Compatibility
Always verify that the kit is compatible with your specific chainsaw model and series, as bore diameter and engine design vary substantially across brands and models. Most manufacturers list OEM replacement part numbers for precision matching.
Bore Diameter
Big bore kits range from about 44mm to 56mm or more. Increasing the bore diameter enlarges engine displacement, enhancing power output. However, compatibility with your chainsaw’s engine block and crankshaft must be confirmed to avoid fitment issues.
Material and Coating
Nikasil-coated cylinders provide superior wear resistance and heat dissipation compared to bare aluminum, increasing the longevity and performance of your engine upgrade. Kits featuring chrome-plated pistons also improve durability.
Included Components
Some kits include just the cylinder and piston, while others offer comprehensive packages with gaskets, oil seals, needle bearings, spark plugs, decompression valves, and sometimes crankshafts. More complete kits simplify installation and ensure all worn parts are replaced.
Engine Performance and Use Case
Consider your chainsaw usage intensity. Heavy-duty professional work benefits from larger bore sizes and comprehensive kits, while occasional users may prefer simpler upgrades that balance cost and performance enhancement.
Installation Complexity
Big bore kits range from straightforward swaps to more involved engine rebuilds. Ensure you have the mechanical skills or professional support before purchasing comprehensive kits containing crankshafts and multiple gaskets.
Brand Reputation and Warranty
Choose kits from reputable manufacturers known for quality engine parts. Check for warranties or guarantees that provide replacement or support in case of defects or fitment issues.
By balancing these factors, you can make an informed decision to upgrade your chainsaw’s power, efficiency, and durability with a high-quality big bore kit that fits your specific requirements.