Vortex VTJ 125cc OK-Junior Racing Engine

The VTJ is the new engine in the Vortex range - CIK-FIA homologated - designed for national and international competitions in the OKJ category, the Junior class of Direct Drive karts established by FIA Karting. Successor of the DTJ (the engine that won two world championships in the three-year period 2020-21-22), the VTJ inherits all its structural and design features at the basis of the successes gained: compact dimensions, low centre of gravity, lightness, ease of management and use, effective mass layout and reliability. Clearly, the parameters required for engine compliance remain unchanged: above all, the maximum speed set at 14,000 rpm. Beside this, however, the VTJ has several new features.

Specifications

Features

• Cylinder with fully machined cast iron liner (dry liner)
• Number of cylinder/crankase transfer: 5/3
• Crankase reed valve intake
• Fully machined intake section and transfers
• connecting rod center to center distance: 102 mm

Manufacturer data: vortex-engines.com · retrieved 2026-09-05