Homemade AWD kit transforms KTM’s 990 Adventure bike
Projekt DT-A is the brainchild of a German engineer, who designed an all-wheel-drive off-roader based on a KTM 990 Adventure. Fitted with a proprietary frame and front swingarm, the prototype adopts a mechanical front transmission system engineered for a no-compromise adventure ride.
Guido Koch, a self-employed mechanical engineer from Germany, has enjoyed riding his off-road motorcycles as far off the beaten track as possible for years and, apparently, more than once he found himself pondering how an all-wheel-drive (AWD) kit would have helped him get out of a difficult situation, such as sticking a fully loaded motorcycle knee-deep in the mud in the middle of nowhere.
Two-wheel-driven motorcycles have been around for decades, with Rokon's Trail Breaker stemming from the late 1960s as the most famous example. Although this tiny American trail bike has managed to build a myth around its name and is still in production to this day, most motorcycle manufacturers have yet to come up with mass-produced AWD kits.
One notable exception would be Christini's mechanical system that has been on offer for several years as an add-on kit for select Honda and KTM off-road models, while recently the American company sells complete AWD motorcycles, and also offers the kit for very special custom builds.
Yamaha has also experimented with two-wheel-drive technology, in partnership with Öhlins and its patented hydraulic system. During the early 2000s Yamaha produced a limited number of WR450F 2-Trac production models and even raced some prototypes at the Dakar Rally, while it also toyed with the same principle on the YZF-R1 superbike.
KTM relied on a similar hydraulic system during its own experimentation with AWD motorcycles, too, only to come to the conclusion that the added 6 kg (13.2 lb) outweighed any possible benefits.
For Guido Koch, all this meant that a factory AWD motorcycle was practically out of the question, especially in the case of big adventurers, like the KTM 990. Challenge accepted.
Koch started designing his dream adventurer almost 10 years ago, and in the process he practically built an all-but-brand-new motorcycle himself. The only parts that remain from the original donor bike are the engine, brakes, rear swingarm and rear wheel; everything else has been designed and manufactured by Koch.
The Projekt DT-A is set up around a purpose-built trellis frame and a front swingarm in place of the traditional inverted forks of the KTM. Power is transmitted via a belt and chain combo, with a secondary cog feeding the front system directly from the gearbox output shaft.
The front setup uses two ball-and-socket joints, one above the wheel that's responsible for steering input and another for driving the wheel. The latter is described as a constant velocity joint, especially designed by Koch for low friction and allowing for a hefty 35-degree steering angle.
The AWD kit relies on a free wheel clutch that engages the front transmission only once the rear slips by more than five percent, while it can be deactivated through a lever on the handlebars when not needed.
According to Koch the working prototype offers a series of advantages. For starters, it shaves off some 40 kg (88.2 lb) over the original motorcycle, despite the fact that it hosts three fuel tanks measuring up to a total capacity of 27 l (7.1 gal).
The Projekt DT-A's front system is described as offering more sensitivity than conventional forks, and at the same time it considerably reduces the steered masses. What's probably the most important benefit from this setup though is the fact that most of the transmission system does not turn with the steering.
One problem with AWD kits for motorcycles is that rotating masses mounted on the front forks create unwanted reactions to the steering input, and it is for this reason that most of the kits in existence do not employ a chain drive all the way to the front wheel hub.
It may not be a big deal for the anemic engine of the Rokon, but for big off-road and adventure bikes that need to push some serious horsepower to the front wheel along very long forks this would be a significant problem, so Christini opted for long spiral rods to transfer power from the steering plate down to the wheel, while Öhlins' hydraulic setup got rid of rotating masses on the forks completely .
In the DT-A's case, Koch elected to load the bulk of the front power-feeding mechanism on the left side of the swingarm, and to this end he preferred to design his own joint, rather than simply choosing an off-the-shelf part from the automotive industry.
As for the future of his project, Koch reveals that all the designs and molds for recreating every part of the Projekt DT-A are waiting for an investor to take it to the next level, which is mass production.
The unavoidable fact is that this transformation kit requires changing most of the original donor KTM, so it is neither simple to apply, nor does it sound cheap. As much as it may be a marvel of homemade engineering, its own intrusive nature makes its chances for mass production appear a bit on the slim side. On the other hand, the absence of similar kits in the market could actually make it as a realistic alternative to Christini's AWD kit.
That is, unless we take the easy way out by fitting electric hub motors to do the deal.
Source: Projekt DT-A