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Wiseco Piston Kit with Gaskets 40mm Bore for Yamaha PW50 1981-2025 PK1157

Part Number: 09030275
WISECO
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SKU:
09030275
MPN:
PK1157
Condition:
New
Availability:
Ships Same Business Day
Weight:
0.65 LBS
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$171.95
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Description

A worn or damaged piston directly throttles your PW50's performance, causing compression loss, poor throttle response, and accelerated engine wear. The Wiseco PK1157 restores full compression integrity and thermal efficiency with precision-forged internals—essential whether you're rebuilding after years of trail riding or optimizing an existing engine. This complete kit eliminates sourcing multiple components separately, giving you everything needed for a professional top-end rebuild in one box.

  • Bore diameter: 40mm
  • Material: Forged aluminum alloy
  • Includes: Pistons, rings, wrist pin, circlips, gaskets
  • Fitment: Yamaha PW50 (1981–2025)
  • Installation: Bolt-on top-end replacement
  • Heat-treated for thermal stability
  • Optimized ring groove design
  • OEM-equivalent precision tolerances
  • Enhanced compression sealing
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Specs

BORE SIZE METRIC:
40.00 MM
PRODUCT NAME:
REBUILD KIT
TYPE:
TOP END
COOLING SYSTEM:
AIR COOLED
DISPLACEMENT:
49 CC
PISTON MATERIAL:
ALUMINUM
PISTON MATERIAL:
FORGED
RIDING STYLE:
OFF-ROAD
STROKE LENGTH METRIC:
39.20 MM
UNITS:
EACH
BORE - OVERSIZE:
STANDARD
BORE - OVERSIZE METRIC:
STANDARD
MODEL:
RACER'S CHOICE
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Fitment

Fitment for Wiseco Piston Kit with Gaskets 40mm Bore for Yamaha PW50 1981-2025 PK1157

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