A chat with... Roland Holzner

An extract of the interview to Engineer Holzner, the person behind Maxter’s remarkable technical re-launch; success is also guaranteed by all his years of experience on working with high performing 2-stroke engines.

His curriculum almost puts us in awe. 2-stroke engines hold no secrets from him and, now all his know-how is available for Maxter, not only an expert in engine design but also in re-organising production and quality control systems.

Mr. Holzner, the press almost overlooked the move you have made, your work experience though, places you with the best engine designers out, especially for 2-stroke. Where did you start from in this new work experience?
There are 3 main points in this programme. The first concerns factory organisation, production lines, defining a proper technical office, workshops and test rooms introducing a rigorous quality system.
The next step was to look into the KF class, while at the moment we’re about to finish the new KZ.  

Let’s talk about the new Twin Torpedo, the one technically tested last month.
At first, we did a mechanical test on all the components, from the driving shaft to gears. After we went on to work out an accurate general balance.  

Can you tell us a bit more?
General balance concerns all the details involved in reducing vibrations, of any type, and inputs produced by the moving elements and transmitted to the kart chassis, on which the engine, differently to Grand Prix motorbikes, for example, is firmly mounted, without any intermediate reducing elements. This influences the carburettor’s response enormously.
There is, though, also another parameter, the driving shaft inertia.

Why is this so important?   
Because it influences the way the combustion chamber fills

Electronics is fundamental for you; could it be the solution required for solving problems concerning the 2-stroke engine?
I quite think so. Apart from ignition, the great challenge remains; electronic injection, now being studied by several manufacturers for some years, from different points. Don’t forget that Honda was one of the first and they developed a 2-stroke (!) for the Paris –Dakar many years ago. When I was with Rotax, I used to work on this, also thanks to the extraordinary interest in applied research on behalf of this Austrian firm, it was no other than the Mercedes that asked us to work on the research of a 2-stroke with no casing pump. Aprilia too has had good results with its DiTech, always connected with the Orbital patent.
The main problem is that if fuel is inject before the exhaust shuts you lose the effect of electronic injection, while if it happens with ports shut there’s very little time for the right combustion to occur. These problems, however, that can be solved.

Get the full interview on Vroom International July issue