Hyceker 47mm Cylinder Piston Top-End Kit for Stihl MS 291 MS 271 (Round Intake) with Bearings & Seals

Hyceker's MS291 MS271 47mm cylinder and piston top-end kit supplies the components needed to rebuild or upgrade the top-end of compatible Stihl MS 291 and MS 271 chainsaws with a round clamp-style intake.

This top-end rebuild kit bundles a 47mm big-bore cylinder and matching piston with bearings, seals and several installation parts to restore compression and running performance on Stihl MS 291 and MS 271 (Farm Boss) models that use the round clamp-style intake. It replaces OEM reference 1141-020-1206 and includes crankshaft bearings and oil seals so you can complete a comprehensive top-end refresh in one purchase.

Which Stihl models and intake style does this kit fit?

This kit is intended for use on Stihl MS 291 and MS 271 / MS 271C Farm Boss chainsaws that accept a clamp-style (round) intake. It’s the newer 47mm big-bore version designed to be compatible with those specific intake and mounting details—confirm your saw’s intake type before ordering.

• Fits Stihl MS 291 and MS 291C top-end rebuilds
• Compatible with MS 271 and MS 271C (Farm Boss) when using clamp-style round intake
• Not compatible with non-clamp or differently shaped intake ports
• Replaces OEM part number 1141-020-1206

What parts come in the Hyceker top-end kit and why they matter?

The kit includes the critical top-end components needed to reinstall or upgrade a chainsaw cylinder assembly. By supplying bearings, seals, a piston needle bearing, spark plug and e-clip along with the cylinder and piston, the kit reduces the need to source separate parts during a rebuild.

• 1 x 47mm cylinder and piston assembly (big bore)
• 2 x crankshaft ball bearings for crank support
• 2 x crankshaft oil seals to help prevent leakage
• 1 x piston needle bearing, 1 x spark plug, 1 x e-clip for installation

How does the 47mm big-bore design affect performance and installation?

The 47mm cylinder ups the bore size over some stock options and is commonly used as a top-end upgrade to restore or slightly change engine characteristics. Installation requires attention to intake compatibility and proper torqueing and clearances; using the included bearings and seals helps ensure a complete rebuild.

• Big-bore 47mm sizing can change displacement compared to smaller stock cylinders
• Requires clamp-style (round) intake flange—verify fit before installing
• Includes bearings and seals to complete the top-end rebuild without extra parts
• Follow service manual for correct piston-ring gap, torque and break-in procedures

What OEM numbers and replacements does this kit cover?

Hyceker lists direct replacement references to help you confirm compatibility with factory parts. The included items match several common Stihl part numbers for the MS 291 and related models so you can cross-reference your existing components.

• Replaces cylinder part number 1141 020 1206 / 1141-020-1206
• Includes bearings that correspond to 9523 003 4304 (crankshaft bearings)
• Includes oil seals that correspond to 9639 003 1585 (crankshaft seals)
• Complete package list provided to match what a top-end rebuild requires

Who is this for: This Hyceker MS291 MS271 47mm cylinder piston kit is aimed at homeowners, arborists and small‑fleet mechanics who need a ready-made top-end rebuild or upgrade for Stihl MS 291 / MS 271 Farm Boss chainsaws with a round clamp-style intake. If you plan to do the rebuild yourself or supply all parts to a professional, this complete kit cuts time sourcing components; if you aren’t sure about intake style or installation steps, consult your service manual or a qualified technician before fitting.