Wunderlich Suspension Test: Precision Meets Electronics

Track photos by pixelrace.de

Wunderlich is already a well-known name in the accessory sector, with a focus on BMW. However, in recent years, Wunderlich has also heavily invested in the suspension sector in collaboration with TracTive Suspension, developing highly innovative solutions. Particularly in the electronic suspension segment, they've now created a solution that allows the replacement of OEM suspension components with optimized ones without triggering error messages.

This is achieved by using a solenoid valve that operates with the same connections and power supplies as the original components. As a result, the electronics don't detect any difference, preventing potential error messages. Diagnostic capabilities are also maintained, which facilitates servicing at a regular motorcycle dealer.

Since the solenoid valve has a different design, the damping can be adjusted with the same power supply. However, the control algorithm of the suspension electronics remains as pre-programmed in the series. This is a point that even suspension manufacturers cannot easily change, as it would require access to and modification of the internal suspension ECU.

To enable adjustments in this area as well, Wunderlich takes a very pragmatic approach by equipping the solenoid valve with an additional conventional damping piston with suitable shim settings to allow for optimizations. In combination with mechanical adjusters on the reservoir, damping can also be modified in the traditional manner using an Allen key. The electronic adjustment options via the display are, of course, retained and can be changed during riding, just like in the series. Essentially, they blend the advantages of both worlds.

And why do this? Well, electronic suspensions, especially those using electromagnetic valves, offer a very wide adjustment range, capable of reaching any value within just 10 milliseconds. In simple terms, a needle in a bore controls the damping. To achieve a damping characteristic similar to a conventional system, the needle must move to different positions at varying compression speeds. This requires a very complex control process, where compression speeds must be detected and considered. Due to the still somewhat limited experience, it's not that easy to optimize a suspension electronically for all operating conditions. This became evident with the first fully electronic suspensions like on the HP4. Particularly in extreme areas like racing, limits were quickly reached that couldn't be easily resolved. Therefore, in these scenarios, the approach has often been to retrofit well-established and proven damping systems with pistons and settings.

By combining these two systems, Wunderlich suspensions now merge their advantages, and to showcase this, Wunderlich organized an extensive test ride. Four motorcycles from various classes were equipped with the electronic retrofit suspensions and brought to the ultimate test track - the Nordschleife. This 20 km track cuts through the Eifel and is instantly recognizable to anyone even remotely involved with motorsports. With its diverse curves, extreme gradients, blind corners, and varied surfaces, newcomers quickly understand why it's called the "Green Hell." Since the track has become nearly inaccessible to motorcycles recently, Wunderlich, in collaboration with ADAC and Doc Scholl, made this legendary test ride possible.

First, I was able to put in a few laps on the S1000RR with electronic suspension, BMW's superbike. Making improvements here is no easy feat since the stock suspension already does a commendable job and the RR's basic geometry provides a lot of stability. However, there are still situations, especially in extreme riding conditions like hard acceleration from deep lean angles or cornering at maximum braking, where suspensions need to meet criteria beyond everyday usability. This is where suspension tuning comes into play. In these subtle areas, you do notice, albeit small, differences. As a now gray-haired ex-racer and suspension technician, I'm pleased that alongside electronic adjustments, I also have mechanical adjusters available for on-site tuning. These are noticeable as well; adjusting them visibly shifts the damping range in addition to the electronic regulation. For instance, on the Nordschleife, I found some damping settings a bit too harsh, but this was easily mitigated by adjusting the compression adjusters. The same applies to the fork. Wunderlich not only offers shocks but also complete electronic closed cartridge kits that replace the stock fork internals, providing the same options as the shocks.

After the RR, I also rode the M1000R, which was equipped with the modified suspension as well. This bike isn't exactly calm at particularly high speeds and tends to exhibit slight steering wobble in its stock form. The suspension upgrade helps improve stability somewhat, but it's conceptually impossible to achieve RR-like handling. Even with optimal functionality, the suspensions can't turn it into a superbike. Nevertheless, the Wunderlich components make the bike more predictable and enhance transparency in the previously mentioned extreme conditions.

In addition to the sporty "R" and "RR" bikes, there was also the opportunity to test the suspensions on the M1000XR, the touring-friendly and comfort-oriented four-cylinder, and the BMW Boxer 1250 GS. I must say, the differences here were significant and noticeable for every rider. These motorcycles are fundamentally designed for comfort and have suspension setups to match in their stock form. However, if you want to push them hard on twisty backroads or even the track, you'll quickly find yourself in motion even in the sportiest setting, missing the necessary feedback in the critical range.

In this case, the Wunderlich suspensions offer a significant improvement and transform the XR and even the GS into track-ready versions. This was impressively demonstrated by Frank Hoffmann, the technical development manager, who showcased his deep knowledge of the Nordschleife by setting the pace with the GS. With his extensive experience in the suspension field, he plays a crucial role in the design of these systems. He is further supported by a seasoned racer and my former IDM teammate, Stefan Nebel, who also proved that he still knows how to handle a motorcycle at speed. He is an excellent addition and has been a part of the development process at Wunderlich for many years. Riding with Stefan was like a flashback to a very enjoyable time together. Therefore, it was not just a test for me, but also a meeting with some very nice people. This good atmosphere is evident among all involved, providing a great foundation for successful development.

Over the course of two days, Wunderlich demonstrated that they are not only proficient in basic motorcycle accessories but have also made a significant leap towards high-quality suspension components. While their primary focus is on BMW, Wunderlich can offer suspension systems for many other motorcycle brands in various forms. Regardless of the actual function, the new electronic suspensions from Wunderlich can be tailored to almost any rider's preferences, making electronically controlled suspensions much more track-ready. When ordering, a basic setup can be tailored at delivery by specifying the rider's preferences, weight, and intended use.

Thus, another global player in the suspension sector is ready to take off, and it's worth taking a closer look at Wunderlich's model list: Wunderlich Online Shop.