If you are rebuilding a snowmobile engine, these kits cover popular models and include the essential components like pistons, rings, gaskets, and bearings. The best choice depends on your engine’s make, model, and bore size. This guide highlights five kits chosen for compatibility, completeness, and practical use for common sled platforms.
| Product | Compatible Engine / Bore | Best For |
|---|---|---|
| SPI 2 Stock Bore Piston Kits | Ski-Doo 670 HO, 78mm | Ski-Doo riders needing a full gasket set with pistons |
| NICHE Polaris Stock Piston Kit | Polaris Classic 500 and various 800/600 applications (OEM compatibility) | Polaris owners seeking OEM-like fit across several model years |
| Mikuni Carburetor Rebuild Kit for Ski-Doo TM40 | Ski-Doo snowmobiles with Mikuni TM40 carbs | Sleds needing carb service without jets/needles included |
| Top End Rebuild Kit Dual Ring for MXZ 800 | Ski-Doo MXZ 800 (2000-2007), 82mm standard bore | MXZ 800 owners performing top-end rebuilds with pistons and gaskets |
| NICHE 80mm Cylinder Piston Gasket Kit for Polaris | Polaris 800cc touring/X2 and related models (multiple parts) | Polaris owners needing 80mm bore components and gaskets |
SPI 2 Stock Bore Piston Kits for Ski-Doo 670 HO
Best for Ski-Doo owners rebuilding a 670 HO engine with a 78mm bore. This kit includes two pistons, ring sets, wrist pins, circlips, bearings, and a full gasket kit. It uses a T-Moly coating with Teflon-Molybdenum treatment to help wear resistance. Choose this if you want a complete, plug-and-play top-end rebuild for the listed 1998–1999 model year range. A potential limitation is that the kit is specific to 78mm bore and may not fit other bore sizes without modification.
NICHE Polaris Stock Piston Kit
Best for Polaris classic and modern 800cc sleds requiring OEM-style piston kits. The kit lists compatibility with several Polaris part numbers and model ranges, including Classic 500 Touring, Classic 550, Scrambler 400, and multiple 800-series platforms. It’s suitable for riders prioritizing factory-fit pistons and matching gasket interfaces. A limitation to watch: detailed compatibility varies by model year; verify bore and engine family before purchase.
Mikuni Carburetor Rebuild Kit for Ski-Doo TM40
This rebuild kit is designed for Ski-Doo snowmobiles using Mikuni TM40 carburetors. Note that the kit does not include main jets, pilot jets, or needle assemblies, due to model variations. Best for owners who are performing a carburetor service and already have or can source the jets and needles separately. Avoid this kit if you need a complete carburetor overhaul with jets included.
Top End Rebuild Kit for Ski-Doo MXZ 800 (2000-2007)
Best for MXZ 800 riders performing a top-end rebuild. The kit includes two piston kits, one top-end gasket kit, two wrist pin bearings, and standard 82mm pistons. It emphasizes high-quality cast pistons and dedicated tooling. This choice is well-suited for those seeking a ready-to-install top-end package, but verify bore size matches the engine before ordering.
NICHE 80mm Cylinder Piston Gasket Kit for Polaris
Best for Polaris 800cc platforms needing an 80mm bore component set, including compatible cylinder, piston, and various gaskets. This kit targets multiple Sportsman and Touring models from 2005–2009 ranges. Choose this if your rebuild calls for an 80mm bore and a coordinated gasket/piston set. A potential limitation is that exact compatibility depends on specific engine configurations; confirm bore and part numbers first.
Buying Guide: Key Considerations for Snowmobile Rebuild Kits
What bore size does your engine require? Bore compatibility is critical for pistons and cylinders. Check the exact bore dimension (e.g., 78mm, 80mm, 82mm) and ensure it matches your engine’s specifications.
Which models are supported by the kit? Some kits list broad Polaris or Ski-Doo model ranges. Verify you are ordering a kit designed for your exact sled year and model family.
Does the kit include all essential components? Top-end kits may include pistons, rings, wrist pins, bearings, and gaskets, while carburetor kits may omit jets or needles depending on model variations. Plan to source any missing pieces if needed.
Quality and coating matter. High-quality pistons and gasket materials improve reliability under cold-start and high-load conditions. Look for coatings like Teflon-Molybdenum when listed.
Installation considerations. Some kits require additional parts or specific tools. Ensure you have the correct tools and reference the engine’s service manual or manufacturer specs during install.
Why Choose One Kit Over Another?
For Ski-Doo owners with a 670 HO, the SPI kit offers a complete top-end set tailored to the 78mm bore, making it a strong all-in-one option. For Polaris riders with Classic or 800-series engines, NICHE kits provide OEM-aligned components across multiple model years, which helps maintain proper tolerances. If carburetion is the focus, Mikuni’s TM40 rebuild kit targets those carbs but requires you to source jets separately. MXZ 800 users benefit from a bundled top-end rebuild kit with standard bore pistons. Finally, the NICHE 80mm cylinder kit is ideal when an 80mm bore is required across several Polaris platforms.
Frequently Asked Questions
- What should I verify before buying a rebuild kit? Confirm bore size, model compatibility, and whether the kit includes gaskets, bearings, and necessary hardware for your engine.
- Do carburetor rebuild kits always include jets? Not always. Some kits omit jets, needles, or pilot jets due to model variations; check the product details.
- Is a complete gasket kit necessary for every rebuild? For top-end or full engine rebuilds, a full gasket kit ensures proper sealing and longer-term reliability.
- Can I mix parts from different brands? It’s best to use brand-specific kits when possible to maintain compatibility and fit, but cross-check part numbers with your engine spec.
- How do I know which bore size I need? Refer to your engine’s service manual or stamped bore specification on the cylinder/barrel.
- Are these kits suitable for all snowmobiles within a model line? No. Always confirm year, model, and engine family to ensure proper fit and function.