Interview of the Month: The man behind the offroad engines

Michael Viertlmayr has been influencing the development of KTM’s offroad engines for years.

He’s worked for KTM for nearly 11 years, and was the project leader of the engine that took the Austrian manufacturer to its first Supercross success, but the latest challenge has been of real magnitude for Michael Viertlmayr, KTM R&D’s Head of Engine Offroad and Motocross, as the world’s first serial production fuel-injection offroad competition bikes begin to hit dealer floors around the world.

Michael Viertlmayr (AUT) 2017

Fascinated by motorcycles by the age of 12 thanks to a cousin who was racing Motocross and Supermoto, Viertlmayr’s obsession with modification and engine tweaking began aged 16 when he got his first moped that was tuned to the moon to be ridden around with groups of friends.

“By the time I was 18 I already had my first KTM, which was a 500 LC4 MY91 with a big bore cylinder, maybe I shouldn’t talk about that (laughs), but it was a tuned one. I rode this bike for one year. I went on to buy a 250 2-stroke, and then started to ride Enduro a little more. From then on I raced to Austrian regional level, some championships and it was a fun time. I was nearly always racing a KTM, so in the last 22 years I was very much a fan of the orange brand,” said Viertlmayr.

Originally from Lower Austria, the enthusiastic engine tuner left high school for a year in the Austrian army before beginning his studies in mechanical engineering at the Technical University in Vienna, followed by a masters in 2005. A year working at the test bench facility at the university was followed by an opportunity that the Austrian grasped with both hands, when he joined KTM as project leader of the ATV engines that were produced at that time in 2006. Just 12 months on Michael worked on his first motorcycle topic as the project leader of the 70 degree Husaberg engine.

“It was a big responsibility; I was very lucky to have the job. I really made my hobby my profession – sometimes it’s about being in the right place at the right time, and after eight years studying it was a perfect opportunity.”

“After the Husaberg project I then worked on the KTM 450 / 500 engine base. At the time there were rumors that KTM wanted to increase its engagement in Supercross racing in the US, but we still were missing the necessary engine. The double cam engines of the time were quite heavy, very complicated and we needed to look at creating another engine base. I was convinced in the direction we should go, by taking a lightweight, less complex Enduro engine and converting it into a Motocross engine. In 2013 we delivered this, and Ryan Dungey immediately began to show his potential. This base has won a lot of races since, and that gives us a lot of satisfaction,” explained Viertlmayr.

Ryan Dungey (USA) KTM 450 SX-F Las Vegas (USA) 2017

During the engine development process the biggest challenge is certainly overcoming the problems that occur when the project is heading from the development to the production stage. There are always situations that arise to overcome, and in recent times it was of course the new 2-stroke fuel injection project that KTM had at the top of its offroad priority list. It needed to happen, it needed to work, and it needed to be ready for this year. It needed to be READY TO RACE too.

With so many displacements and models in the KTM offroad range, the R&D department based in Mattighofen is always busy. With four project leaders in Viertlmayr’s offroad engine development department, and a cycle of three years for each engine family, there is always a lot of work to do. Reaching the point of production for the 2-stroke TPI machines is certainly a big milestone for KTM after 13 years developing this technology.

Michael Viertlmayr (AUT) 2017

“It feels fantastic to bring the bike to production. It’s a big team effort, and we have to thank the project leader of the engine Bernd Holzleitner, who was responsible for tuning the engine base for the TPI. I would really like to give the credit to their work, because I was just helping to put it all together to bring the right people to the table at the right time to discuss topics and maybe give some rough directions, but the major work was done by the core team. The EMS guys did a great job on this – Michael Derntl, Phillipp Indlekofer, and Stefan Spatzenegger, they did an amazing job.”

“We decided to start with the best-selling models of the 2-strokes, and because we needed to achieve this for homologation, but now we’re thinking of different displacements where we can use this technology and also new models. This is undecided for the future, and we will see what happens with the regulations in Motocross and Enduro.”

“The initial feedback on the KTM EXC TPI machines has been great from the recent launch at Erzberg, and we still have a lot of possibilities to consider. Our main focus was to at least equal performance of the carbureted models, improve the rideability with the possibilities of fuel injection, while retaining the 2-stroke smell and feel as well as considering the READY TO RACE approach.”

KTM EXC TPI Erzberg (AUT) 2017

From a motivation point of view of course the goal, as Viertlmayr explains, is to retain the READY TO RACE delivery of these machines right out of the crate. The close relationship with motorsports is an important one when it comes to development of all offroad models.

“Our biggest motivation of course is our success on the track; the feeling when we’re watching on our screens at the weekend our riders winning. On a weekend we may watch the Supercross, or MXGP, and when everyone is back in the office on a Monday that’s what the talk is – this holds together the team well and is a big motivation for us to make competitive engines, because the race bikes are not that different from the stock bikes. We’re in very close contact with the race teams, they are our friends and we have a close relationship!”

Finally, we asked Michael if he had a choice of any bike … what would he buy?

“I don’t ride street anymore, so my favorite bike out of the whole range would be the KTM 300 EXC TPI or the KTM 500 EXC-F!” He clearly likes a lot of power then!

Photos: KTM