Motorcycle: Safe in the Saddle

Author: Joachim Geiger

Nov 09, 2022 Safety on the road

Smart motorcyclists know their limits. Electronic safety personnel is therefore always welcome on board. We spoke to DEKRA motorbike expert Luigi Ancona about current assistance systems.

Motorbikes stand for freedom and riding pleasure like no other means of transport. With enough horses under the saddle, feelings of happiness can set in when a spirited twist of the throttle catapults the bike to the limits. On the other hand, motorcycling is dangerous. After all, leaves on the road, an obstacle in a curve, or the carelessness of other road users can quickly put an end to the unity of man and machine. “Accident statistics show that drivers of registered motorcycles are particularly at risk on rural roads. Typical errors are inappropriate speed, not keeping enough distance, and making mistakes when overtaking,” says DEKRA accident researcher Luigi Ancona. So when things get critical, the support of on-board electronic “safety personnel” is vital.
Electronic driver assistance systems: Every biker’s best friends
In fact, rider assistance systems have a good reputation in the biker scene, as the Institute for Two-Wheeler Safety (ifz) in Essen found in a study published in 2020. According to the study, over 60 percent of the motorcyclists surveyed believe that electronic systems help to reduce the number of accidents. More than half admit that safety-relevant equipment played a decisive role in their choice of motorbike. For motorbike expert Ancona, it is also obvious that electronic assistance systems offer tangible added value to both inexperienced riders and old hands alike, by mitigating the risk of a crash when braking, accelerating, and leaning. However, the residual risk remains high: While a car’s four wheels usually ensure a solid grip when a safety system kicks in, different conditions apply to motorbikes in terms of driving dynamics and controllability by the rider.
Can an automatic emergency braking system work?
Electronic assistance systems cannot simply be transferred from a passenger car to a single-track vehicle. An automatic emergency braking system, for example, is an enormous challenge for vehicle developers because the driver must always keep his bike balanced, even under regular circumstances. Two studies commissioned by the German Federal Highway Research Institute (BASt) show that a technical brake assistance system for speeds up to 70 km/h could significantly reduce braking distances in an emergency. Almost half the initial speed can supposedly be reduced before the driver is even able to intervene. So there is still room for improvement in the development of new assistance systems. Could the end-all of innovation perhaps even be a fully automated motorbike? Manufacturers like Honda and BMW have already caused a stir with self-driving prototypes at the Consumer Electronics Show (CES) in Las Vegas, USA. However, the idea that a motorbike can take on a mountain pass all by itself is probably anathema for most bikers – assistance systems are always welcome, but riders still want to make their own driving decisions, thank you very much. Nevertheless, such experiments show that the industry still has plenty of ideas in store with its systems for motorbikes.
Radar-based systems ensure a safe distance
Honda, for example, has just secured the patent for a lane departure warning system for motorbikes. Radar-based systems that automatically maintain a safe distance to the vehicle in front by adjusting the speed of the motorbike are also on the rise. In addition, the spectrum of assistance systems ranges from anti-lock braking systems (ABS), semi-active suspensions, and tire pressure monitoring, to adaptive brake lights, hill-start assist, and shift assist. Lights are also becoming intelligent. For example, supplier Continental has developed a headlight assistant that detects oncoming traffic and traffic ahead, and automatically switches to optimal lighting so as not to dazzle other road users.
ABS is popular as an active safety system
For many bikers, however, the number one assistance system is the well-proven anti-lock braking system. “ABS is a game changer in terms of rider safety on motorcycles,” emphasizes DEKRA expert Luigi Ancona. European lawmakers are also allowing for its importance: Since January 1, 2017, a standard anti-lock braking system has been mandatory for the first registration of motorcycles with a displacement of more than 125 cubic centimeters and a power output of more than eleven kilowatts. Since then, manufacturers and suppliers have significantly enhanced this basic safety technology. In addition to ABS sensors for balancing the speeds of the front and rear wheels, lean angle sensors are increasingly coming into play, enabling new control functions. “Cornering ABS is the next milestone in safety technology,” reports Luigi Ancona. “The system applies the correct brake pressure to the front and rear wheels in a fraction of a second, depending on the lean angle.” Unlike classic ABS, it reduces the pitching moment during heavy braking when cornering and can prevent the motorcycle from slipping away in the critical limit range. As a result, the bike can continue to follow its cornering line.
The driver’s limits are coming into focus
Another pillar of rider safety is the traction control system, which prevents the rear wheel from spinning even when the vehicle is on an incline or a slippery surface. A rear wheel that lifts off during braking (stoppie) and a front wheel that rises during acceleration (wheelie) can also be kept in check with the help of the ABS and TCS functions. In the case of stoppie control, the system reduces the brake pressure on the front wheel to such an extent that the rear wheel retains traction. In wheelie control, on the other hand, the engine control system reduces power until the front wheel is back on the ground. Meanwhile, the focus is also increasingly shifting to motorcyclists’ limits. In a research project, technology group Bosch is investigating how to prevent sudden lateral slipping in a curve. The safety system, which was first presented four years ago, works with a gas pressure accumulator that suddenly empties when the specified limit is exceeded and the resulting recoil causes the two-wheeler to straighten up again.