CRANKSHAFT BOTTOM KIT 03-25 YZ250, WISECO WPC134 FULL ASSEMBLY
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Wiseco Crankshaft Bottom End Full Assembly WPC134. Precision-trued to OEM specifications and factory assembled. Connecting rods are double-forged to maintain superior dimensional consistency through improved grain flow. Shot-peening eliminates residual stresses and smoothly blends the rod forging surfaces. Corrosion-resistant surface treatment. Top and bottom end rod bores case hardened to 58-62 RC to optimize bearing running surface. Crank pin bearing radial running clearance is optimized to ensure maximum performance. Precision honing ensures ultra-round bearing surface. Precision-engineered oiling slots maximize rod strength and bearing life. Double-drilled small ends provide the piston pin with extra lubrication and cooling, reducing distortion of top end due to thermal transfer from the piston. Silver-coated bronze phosphor thrust washers with dimpled design increase oil retention and reduce friction between rod and washer interface. Crank pin bearings are manufactured with the highest-quality hot-rolled steel case hardened to 58-62 RC.
- SKU
- 56-186.WI
- Brand
- Wiseco
- Availability
- In Stock (2)
Fitments (24)
| Make | Model | Year |
|---|---|---|
| YAMAHA | YZ 250 | 2003 |
| YAMAHA | YZ 250 | 2004 |
| YAMAHA | YZ 250 | 2005 |
| YAMAHA | YZ 250 | 2006 |
| YAMAHA | YZ 250 | 2007 |
| YAMAHA | YZ 250 | 2008 |
| YAMAHA | YZ 250 | 2009 |
| YAMAHA | YZ 250 | 2010 |
| YAMAHA | YZ 250 | 2011 |
| YAMAHA | YZ 250 | 2012 |
| YAMAHA | YZ 250 | 2013 |
| YAMAHA | YZ 250 | 2014 |
| YAMAHA | YZ 250 | 2015 |
| YAMAHA | YZ 250 | 2016 |
| YAMAHA | YZ 250 | 2017 |
| YAMAHA | YZ 250 | 2018 |
| YAMAHA | YZ 250 | 2019 |
| YAMAHA | YZ 250 | 2020 |
| YAMAHA | YZ 250 | 2021 |
| YAMAHA | YZ 250X | 2016 |
| YAMAHA | YZ 250X | 2017 |
| YAMAHA | YZ 250X | 2018 |
| YAMAHA | YZ 250X | 2019 |
| YAMAHA | YZ 250X | 2020 |
- General Product Group
- Crankshafts & Parts
- General Product Type
- Crankshaft Bottom End Kits
- Variant Id
- 250191
FULL DESCRIPTION
Wiseco Crankshaft Bottom Assembly WPC134
This Wiseco Crankshaft Bottom Assembly WPC134 is engineered for precision and durability, providing a full assembly for your motorcycle's engine. Each component is designed to meet or exceed OEM specifications for optimal performance and longevity.
Key Features:
- Precision Trued: Crankshaft is trued to OEM specifications for accurate engine operation.
- Double-Forged Connecting Rods: Ensures superior dimensional consistency through improved grain flow.
- Shot-Peened Finish: Eliminates residual stresses and smoothly blends rod forging surfaces for increased strength.
- Corrosion-Resistant Surface Treatment: Protects components from environmental degradation.
- Case-Hardened Bores: Top and bottom end rod bores are case hardened to 58-62 RC for an optimized bearing running surface.
- Optimized Bearing Clearance: Crank pin bearing radial running clearance is precisely set for maximum performance.
- Precision Honing: Ensures an ultra-round bearing surface for smooth operation.
- Engineered Oiling Slots: Maximizes rod strength and bearing life through intelligent oiling channels.
- Double-Drilled Small Ends: Provide enhanced lubrication and cooling for the piston pin, reducing thermal distortion.
- Silver-Coated Bronze Phosphor Thrust Washers: Feature a dimpled design to increase oil retention and reduce friction.
- High-Quality Crank Pin Bearings: Manufactured with the highest-quality hot-rolled steel and case hardened to 58-62 RC.
- Full Assembly: Includes bearings and gaskets for a complete installation.
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Check the fitment table on this page against your make, model and year. Not sure? Call or email us and we will check it for you before you order.
UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details
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