Lexmoto Adrenaline / Valiant 125 K157FMI 57mm Cylinder Kit
Brand-new unbranded standard 57 mm cylinder barrel and piston kit for compatible Lexmoto Adrenaline and Valiant 125 models using the K157FMI engine family.
Key Specifications
- Engine family: K157FMI / 157FMI GS-style
- Displacement: Standard 125cc application
- Standard bore: 57 mm
- Engine stroke reference: 48.8 mm
- Piston-pin reference: 14 mm
- Cooling: Air-cooled
- Engine type: Single-cylinder 4-stroke
- Cylinder style: EGR / secondary-air-system type
- Condition: Brand new
- Type: Unbranded aftermarket replacement
What's Included
- 1 x cylinder barrel
- 1 x piston
- 1 x piston ring set
- Head and base gaskets
Vehicle / Engine Compatibility
| Make | Model / Engine | Years / Scope | Notes |
|---|---|---|---|
| Lexmoto | Adrenaline 125 XFLM125GY-2B | carb model | Official Lexmoto specification: K157FMI, 57 x 48.8 mm |
| Lexmoto | Adrenaline 125 EFI XFLM125GY-2B-E4 | Euro 4 EFI | Official Lexmoto specification: K157FMI, 57 x 48.8 mm |
| Lexmoto | Valiant 125 XF125R | carb model | Official Lexmoto specification: K157FMI, 57 x 48.8 mm |
| Lexmoto | Valiant 125 EFI XF125R-E4 | Euro 4 EFI | Official Lexmoto specification: K157FMI, 57 x 48.8 mm |
Important Fitment Information
Carburetted and EFI versions share the K157FMI 57 x 48.8 mm engine family, but emissions fittings and cylinder details can vary. Match the existing EGR/secondary-air ports, piston and cylinder before ordering.
Do not order by 125cc capacity alone. Before purchase, compare the original engine code, 57 mm bore, piston-pin diameter, piston crown/profile, cylinder height, stud spacing, gasket profile, oil passages and EGR/secondary-air ports with the existing engine.
The K157FMI family was used across carburetted and fuel-injected motorcycles, and production changes can affect top-end components. This kit should only be used where the original parts match the standard 57 mm K157FMI EGR-style configuration.
Installation
Correct piston-ring orientation, piston direction, valve timing, gasket installation and cylinder-head torque are essential. Professional installation is recommended where the correct engine-building procedure is not known.