What is ABS used for on an electric bike?

Bosch ABS 2.0 helps balance braking power across both wheels and helps prevent common crashes related to falls from hard braking. The German equipment manufacturer is betting a lot on this technology and wants to make it accessible to everyone in the years to come. How does it work? To understand it, nothing better than a test.

Bosch is developing ABS technology for e-bikes, which was updated to version 2.0 at the end of 2022 and is starting to be rolled out to high-end bikes from brands like Riese & Müller, Cube, Focus , Kalkhoff or KTM. The goal of this technology is simple: to prevent common bicycle accidents caused by falling situations due to hard braking — for example when you want to avoid an open door in front of you or when the ground is not sticking.

Why do we fall on a bicycle when we brake suddenly?

How does an ABS prevent these falls? Before answering it, we must first understand how braking works. Typically, when braking hard, the rear wheel can lock up, which can cause the bike to slide sideways. Likewise, if the front wheel is locked, it can cause what are known as sunspots, where the rear wheel rises and falling is inevitable, with more or less severity. These two problems have the same origin: one wheel is spinning faster than the other at a given moment (since you are braking on one side or the other).

Bosch ABS 2.0 // Source: Thomas Ancelle for Numerama

In addition, only very rarely do you brake proportionally at the front and rear when you press both brakes. Unconsciously, to avoid a fall due to the sun, you brake a lot more with the rear brake on your bike, which destabilizes the braking. We then forget that braking with the front brake is more effective than braking with the rear brake on a two-wheeler: you should constantly brave the fear of falling and force yourself to use both the front brake and the rear brake .

ABS for electric bikes: how does it work?

For further

Specialized Turbo Vado SL // Source: Louise Audry for Numerama

This is where Bosch ABS comes in to secure braking by harmonizing the braking power on both wheels, in particular on the front wheel on which it acts directly. To work, it combines four technologies. The first is notched discs with regular openings, attached to the brake discs.

The second are camera modules that film these discs to determine their rotation speed (by identifying the speed of passage of the small window inserted at regular intervals). The third is a central unit which calculates the difference in speed between the two wheels, and the last is a solenoid valve which acts on the braking to balance the speed of rotation between the two wheels.

ABS Bosch // Source: Thomas Ancelle for Numerama
ABS Bosch // Source: Thomas Ancelle for Numerama

In practice, you can clearly feel when the ABS is activated: even with the front brake fully on, you notice that the wheel is released for a very short period in order to synchronize its speed of rotation with the rear wheel. We were hesitant at first, but after a few careful brakings, it was impossible for us to fault him. Wet pavement, grass, mud, puddles, slippery ground due to markings on the ground, dirt… nothing could destabilize us during braking. A small screen allows you to see how long and how many meters the bike is stopped.

We pushed the exercise by braking almost only with the front wheel and pounding at very high speed on multiple surfaces (mud that becomes a puddle that becomes grass). The bike remains stable, braking is safe and fast. In short, the technology works and does exactly what Bosch claims: secure dangerous braking. So much so that after 100 km of testing, returning to normal brakes on my personal bike took me some time to adapt.

Ultimately, Bosch has a goal: to lower the price of its ABS to have an accessible model to equip mid-range bikes. The competition is also not wait-and-see: Shimano, Stromer or Bluebrake also have products in the works.

Subscribe to Numerama on Google News to not miss any news!

Source link -100