After world market leader Honda, BMW now also has a motorcycle transmission in its range that takes care of clutching for the driver, but leaves him with the gear lever. For the authentic feeling and “the emotionally important dynamics of the shifting process,” says BMW. Automated Shift Assistant – ASA (Automated Shift Assistant) for short – is what the brand calls its optional gear changing alternative with fully automated clutch actuation, which was certainly not by chance presented as an example in the top-selling BMW R 1300 GS.
BMW’s new transmission assistant is based on the in-house Shift Assistant Pro (clutch-free gear changes while driving) and essentially merges two transmission models: Honda’s DCT dual-clutch transmission and the E-Clutch electronic clutch recently presented by the world’s largest engine manufacturer. This means: engage first gear, drive away, shift up and down, stop – all of this now works at BMW without having to pull the clutch and thus like the new development from Honda. The left lever disappears. Unlike the Japanese, the Bavarians throw the clutch lever completely overboard. Instead, there is just a small button on the left of the handlebar. The rider uses this to decide whether he wants to change gears by foot (“M” for manual) or transfer the shifting work entirely to the bike’s electronics (“D” for Drive). The automated gearshift assistant can also change gears independently – just like Honda’s DCT. The goal in both cases: more driving pleasure – through less distraction and smooth shifting. “Optimally selected gear changes create a new driving feeling with a more intense driving experience,” promises BMW for the algorithm in “D” mode. Regardless of whether on a straight road, winding passages or in the city: the right gear is always automatically assigned to the individual desire for propulsion, which leads to harmonious and extremely fluid driving behavior depending on the driving mode. The prerequisite for this is, among other things, a six-axle -Sensor measurement unit (IMU), which almost all premium bikes have these days. The IMU constantly analyzes factors such as acceleration, speed and lean angle and adjusts ABS, traction control and in this case the gear changes accordingly. On the road and off-road. The 145 hp boxer engine from the GS – “but also any other powerful engine from BMW Motorrad,” says product manager Reiner Fings – harmonizes perfectly with the automated gearshift assistant, that was the first impression at the preliminary presentation in the Enduro Park Hechlingen. We were able to drive it ourselves The ASA-GS is not there yet, but it should be there in the second half of 2024. The additional weight of the technology, which is discreetly mounted under the bike, is only 2.1 kilograms. This means that the new ASA transmission is about as heavy as the already available Honda E-Clutch and, according to initial statements from BMW, about as expensive as the competitor’s DCT, but saves the additional technical effort and additional weight of a dual clutch transmission, which is the case a Honda is around eleven kilograms. The new gearshift assistant, which will undoubtedly take motorcycling into a new era, will cost a little more than 1,000 euros extra. This is how the system works. Starting off becomes a playful exercise with the E-Clutch. The gear changes happen smoothly and quickly. Annoying load changes and the shift jerk when upshifting with a manual transmission are almost completely eliminated. BMW is now promising the same. The way the ASA works is reminiscent of a sequential car transmission, explains Reiner Fings, product manager at BMW Motorrad: “Two electronically controlled electromechanical actuators actuate the clutch and the gearshift, thus enabling easy starting and automated switching processes. The driver’s shift request is transmitted to the control via a shift lever sensor that is actuated by the conventional foot shift lever. Additional sensors determine the speed of the transmission input shaft and the clutch position. These values are transmitted to the TCU control unit, which is closely networked with the engine control system. The actuator regulates the required clutch slip, activates the clutch when changing gears and opens it when stopping.”It sounds complex, but it works like itself on the motorcycle: the driver doesn’t notice any of this. He simply accelerates and concentrates on driving and braking. Only Honda has a DCT. It will only be a matter of time before other manufacturers jump on the bandwagon. BMW initially wants to reserve ASA for more powerful machines in the upper displacement segment. Honda is different: The new electronic clutch is first available in the mid-range bikes CB650R and the CBR650R. More models will follow. Unlike the DCT, the driver basically has to shift up or down himself with his foot. As usual, there is a clutch lever on the handlebars on the left. The driver can use it. Or he leaves it alone. Shift shocks when changing gears are prevented by a coordinated combination of half-pressing the clutch and interrupting fuel injection and ignition control. The result is extremely smooth driving behavior. Even when stationary, the driver can easily change through all gears – and even start in a high gear without the risk of slipping if the driver forgets to downshift before stopping at traffic lights. The clutch control itself is carried out – similar to the DCT and the ASA from BMW Motorrad – via an actuator unit, which in this case is located on the right side of the engine together with two small electric servomotors. If the driver pulls the clutch lever from time to time, the Honda E-Clutch is automatically reactivated after a few seconds. Optionally, it can be deactivated for an entire ride using the TFT display and the gears can be changed manually using a trigger switch with plus and minus buttons on the left of the handlebar. A feature for those who are nostalgic for switching gears, one might think, which could be expected to have a similar career at Honda as DCT. In 2010, the Japanese brought the first and so far only mass-produced dual clutch transmission for motorcycles onto the market. The concept is well received: Honda, for example, only offers its Gold Wing luxury tourer, which weighs at least 367 kilograms, with an automated 7-speed transmission. In the successful travel enduro CRF 1100 L Africa Twin, DCT (six speed levels) accounts for a total of more than 55 percent, and in the sports tourer NT 1100, more than half of the customers also opt for assisted shifting. Honda produces models such as the SUV scooter “I want to focus on motorcycling: cornering, feeling the perfect line and timing when braking and accelerating,” says Honda’s DCT chief engineer Dai Arai. If the fact that you don’t have to clutch is enough for you, the E-Clutch is the best choice: it costs a small 400 euros extra. (cen)
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