FELIX KRAHNSTOVER
In 1978 Felix Krahnstover was employed by KTM to work alongside Walther Luft and Heinrich Wieditz to develop the machine. In 2010 Trial Magazine spoke with Felix about his memories of his time at the factory.
Felix joined the team as the rider charged with developing the KTM in competition. He was already the ten-times German Champion and a regular World round competitor. He told us that the development engineer Heinrich Wieditz came from the Zundapp factory, and the whole project was based on Heinrich’s Zundapp frame concept and the bottom end of KTM’s enduro engine. Unfortunately, Heinrich had no idea about trials, but with help from Walther Luft, he could get the engine to develop power wherever it was wanted.
The 240cc engine had more than sufficient power for the trials of the time. If it did have a problem, it was that the power delivery was not as smooth as the Montesa that Felix had been riding before. To calm the enduro power delivery, a number of new sleeves with different porting configurations were tested over the season. They also used a
Bing carburettor which, despite not being as good as the Amal which was the benchmark of the time, did at least stay in tune longer thanks to improved materials.
Given its enduro heritage, the KTM was a little taller and a little wider than was optimum. The suspension was as good as the standard for the time, with Marzocchi front forks and shocks for the rear suspension. Felix mentioned that there were no real innovations introduced during the development as the project was to create a viable machine for sale and, as such, everything was costdriven. There were not the funds available to start with a clean sheet of paper, as many outsiders had first thought.
Clearly, the machine did have pretty good potential though, as Felix finished in 10th place and earned a world championship point at the German round held in May. He also won the German championship once again.
Before starting out on the development project, KTM had asked its worldwide importer network what the potential sales were, and the total came to around 10,000 machines per year. However, before committing to the expensive task of producing tooling, they asked the same question again, and the result was nearer 1,000 units! This effectively killed the project stone dead.
Luft created one of his signature tubular steel frames to house the engine in a double down-tube cradle type frame protected by a Teflon sump guard. It was a very traditional design that used Ceriani front forks and Girling rear shocks with conical wheel hubs, helping with the weight saving. The finished prototype machine weighed only 85kg but appeared to be much heavier as the large, flat-sided aluminium fuel tank, and red paintwork did nothing to help the aesthetics.
READY FOR ACTION
As 1975 drew to a close, the KTM trials model was finally ready for competitive action at the beginning of 1976 season. The attraction of the new KTM trials machine had the trials world waiting in anticipation as they wanted to view the expertise of the Austrian motorcycle manufacturer and the well-founded engineering reputation of Walther Luft. The excellent rider and engineer was to develop the machine in competition during the season, and he competed in a number of trials in Austria, some European championship rounds and the legendary Scottish Six Days Trial, which is deemed as the ultimate testing ground for any trials motorcycle. Even if Walther didn’t break the mould with his riding abilities and technical finesse, he kept the
250T development in a positive direction. Not able to challenge the likes of top riders such as Yrjo Vesterinen, Martin Lampkin, Malcolm Rathmell or Bernie Schreiber he nevertheless managed to finish in a fine 11th position in the final round held in Czechoslovakia.
The 1977 season saw some evolutions, with the appearance of a banana-shaped swinging arm to increase rear suspension travel and more practical polyester fuel tank. The engine received a massive 34mm Bing carburettor and an increase in capacity to 324.7cc with a 78mm bore x 68mm stroke, giving a claimed output of 22bhp @ 6,500rpm.
To help support Walther Luft with the ongoing development, they signed the German champion Felix Krahnstover from Montesa, who at 2.05m tall would make good use of the extra power. He was a good rider who would give KTM more visibility on the international scene, which was rewarded some favourable results.
OFFICIAL PRESENTATION
At the end of the 1977 season at the Milan Show, KTM officially presented the 325T on their show stand. To say that it was pretty would be an exaggeration, but neither was its Spanish rivals. Fantic and SWM had also been attracted to the trials world. They presented their new models which looked very functional, but more importantly, were also cosmetically attractive to the buying public! The KTM was finished in grey and blue with an extended seat and the bigger 324.7cc engine. Technically it had changed; it was tidied up from the prototype with the addition of Marzocchi rear shocks and appeared ready for production even if this was never to be the case.
Krahnstover worked hard throughout the 1977 trials season when he once again became the German Champion, and he took a fine 10th position in his homeworld round which was by far the best result obtained by KTM. The machine had been developed further by the addition of a smaller fuel tank, a new exhaust system and an aluminium swinging arm. It looked very functional, but it was not convincing in the trials world, where fashion is king. Even if the Spanish manufacturers, with their ageing product line, seemed unable to resist the new and ambitious Italian manufacturers, the trials market was judged to be far too small by Erich Trukenpolz who preferred to see his teams concentrate on the core business of motocross and enduro. The boss declared a definitive end to the KTM 325T project at the end of the year.
Trial Magazine would like to thank Eric Kitchen and Ian Lawrie for going that extra ‘mile’ to support this article with some very rare, old pictures: EK, thank you.
“Krahnstover worked hard throughout the 1977 trials season when he once again became the German Champion, and he took a fine 10th position in his homeworld round which was by far the best result obtained by KTM.”