Simplicity. This is the key value behind the new Vortex-ROK DVS engine, which anticipates many of the solutions set to be officialized at the next CIK-FIA homologation with the new OK formula
As of next year, according to federal CIK-FIA guidelines, OK engines will replace the current KF formula in all international race events.
The new name of the game is direct drive with push start, aided by a decompression valve in the cylinder head.
The majority of karters will be introduced to the innovation next season, but drivers who race in the ROK Cup, the one-make series powered by Vortex (OTK group), have already had a chance to try an engine that is a close relative of the new OK. In fact, the Super ROK category has introduced the first engine featuring the new decompression valve system: the DVS. The basis remains the KF, characterized by tried and tested components and validated by a consolidated economy of scale; but several elements and solutions have been changed in a twin spirit of necessity and innovation. TKART has had a chance to analyze the DVS in detail; we opened it up, took photographs from every angle, and talked with the technicians who developed it, getting a good sense of the kind of engine it is.
Let’s start by saying that while we like many of the solutions featured on the DVS, we also we have our doubts regarding others. Then again, for now the DVS is reserved to an adult category, not a junior class, so drivers are able to compensate for some of its limits.
The blue component on the exahust side of the cylinder head is the decompression valve. Here it is in “closed” mode.Below, a shot of what happens inside the engine when it shuts off.
The decompression valve in the “open” position.