Bosch innovates compact motorcycle antilock braking system

Bosch has claimed it has achieved a World first with its new brake control system developed specifically for motorcycles, contradicting the idea that the systems are too big and too heavy to be fitted to two-wheelers. The manufacturer says it has been able to reduce the size and weight of its system to make it suitable for use on motor scooters and small motorcycles, while the flexible design allows Bosch to offer three different levels of system, from the basics to electronically controlled models. The company points out that only 16 per cent of all newly manufactured motorcycles in the EU in 2010 were fitted with ABS; the company says it expects European legislation to impact the market in the next decade, as a proposal has been tabled to make ABS compulsory on new bikes entering the market from 2017.

“At 0.4 litres in size and 700 grams in weight, the current Bosch generation 9 is just over half the size and weight of the predecessor generation. This currently makes it the world’s smallest motorcycle ABS,” says Tobias Fluck, a Bosch expert for motorcycle ABS, who says the latest model is available for every motorbike, from entry-level machines to super-sports models. Generation 9 has been in series production since 2010, and currently features in models made by Kawasaki, BMW, Ducati, and KTM.

At present, if motorcyclists have to brake as quickly as possible in a critical situation, they face a difficult task. On most motorbikes, they have to first of all use the hand and foot brakes separately to control the braking pressure for front and rear wheels. Then they have to prevent the wheels locking up at all costs. The findings of a Bosch study based on GIDAS, the German database of accident statistics say that 47 per cent of motorcycle accidents are caused by wrong and hesitant braking. Bosch argues that the antilock braking system solves this problem, allowing safe braking by preventing the wheels from locking up. This can both prevent a fall and significantly reduce braking distance. Cars have been rolling off the production lines in Europe with ABS as a standard feature since 2004, making the 2010 bike percentage look very modest indeed, considering the safety benefits.

The previous ABS systems of all suppliers were based on passenger-car technology, and were thus comparatively large, Bosh explains. While they could be installed in larger machines, this was often not possible in small motorcycles. In tandem with the development of the new generation of Bosch passenger car brake control systems, the engineers at the Bosch Engineering Centre in Japan worked on the generation 9 for bikes, at half the size of its predecessor. It allows variants to be produced for different ranges of functions, and its design is cost-effective, which is important if it is to be used widely in all motorcycles with hydraulic brake systems.

The ABS 9 base offers full antilock protection helping riders experiencing sudden changes in road surface, caused for example by grit or patches of oil and assisting the braking of inexperienced riders. The ABS 9 plus variant is suitable for powerful machines because it uses an additional pressure sensor, which takes effect even when pressure is being built up during emergency braking. This specifically prevents the rear wheel rising, and thus heads off the risk of flipping over. Meanwhile ABS 9 enhanced, the most powerful version, offers the additional eCBS function, which allows riders to operate just one of the two brakes – front or rear. ABS 9 enhanced automatically applies the second brake without the rider having to apply more pressure and without changing braking strength.

ABS 9 enhanced can help to a moderate degree to stabilise righting moment and banking when braking in an inclined riding position. Looking to the future, Bosch says it will also be able to add more functions to the ABS with eCBS. The company is trialling versions that modulate braking pressure so effectively, even in curves, that the typical motorcycle accident as a result of over-braking the front or rear wheel can be largely ruled out. A controlled intervention in the engine management system is also possible. This opens up the possibility of new functions such as traction control and hill-hold control.

ABS for all motorized two-wheelers from 2017

In 2009, more than 5,000 motorcyclists were killed on Europe’s roads. According to the European Transport Safety Council, the danger of a fatal accident, for the same distance travelled, is 18 times higher for motorcyclists than for car drivers. And according to many scientific studies, ABS is the system with the greatest safety gain for motorcycles. Bosch exemplifies a study presented by Vägverket, the Swedish highways authority, in 2009 that concludes 38 per cent of all accidents involving personal injury and 48 per cent of all serious and fatal accidents could be prevented with the help of ABS.
Bosch’s study based on data from GIDAS concludes that a quarter of all accidents with injuries and fatalities could be prevented if ABS was standard equipment. A further one-third of all accidents with injuries and fatalities could at least be mitigated by the antilock system. In 2010, findings such as these were enough to persuade the EU Commission to propose making ABS mandatory for motorized two-wheelers from 2017. A study of the benefits of ABS conducted by the European Commission shows that more than 5,000 lives could be saved over the next ten years alone if ABS were made mandatory. A decision is expected to be taken this year. But for the emerging markets in Asia and South America as well, ABS promises a significant improvement in road safety. The condition for its use on a wide scale is a hydraulic brake system. In all markets, this standard is becoming more and more established.