The concept of two fingered or covered braking on a motorcycle is a simple one and yet so many riders fail to employ it. Many aren’t taught the technique when learning to ride and we’ve even heard instances where riders are told not to use it because it’s dangerous (more on that later). Yet, by using two fingered braking you can reduce your stopping distance by around 14 feet (4 meters) when travelling at 60 mph. It all comes down to reaction times.
We’ve created a video on reaction time and two fingered braking which you can view below, or read on.
On a bike (or any motorized transport), total stopping distance is a function of the following:
Stopping Distance = Mental Processing Time + Physical Reaction Time + Vehicle Reaction Time
Mental processing time is the time it takes for an individual to perceive that there is something that needs to be reacted to. For example, a rider detecting a car pulling out from a driveway and deciding that they need to brake. The duration of mental processing time varies widely depending on circumstance. If you’re lane splitting in heavy traffic, your mental processing time will be quicker than if you had been riding on a quiet country road for a few hours and all of a sudden an animal runs in front of you from the bush.
Physical reaction time is the time it takes for a person to perform the muscle movement to physically react. In braking while driving a car, the physical reaction time would be the time it takes for a driver to move their foot from the accelerator and then press the brake pedal. Physical reaction time again will vary depending on the situation. Obviously, moving your foot from the accelerator to the brake is going to take longer to do than pull in the clutch lever on a bike if your hand is already on the lever.
In a study by the Promocycle Foundation which we rely heavily on for this article, they found that on average, it takes a rider 0.62 seconds to move their hand from the throttle bar and pull in the brake lever.
The third factor in stopping distance is the vehicle reaction time. Simply put, this is the time it takes for a vehicle to stop once the brakes are engaged. This time will depend on vehicle speed, tires, brake quality and road surface conditions.
So how does two fingered braking reduce stopping time? By reducing the physical time it takes to engage the brakes. Instead of having your fingers wrapped around the throttle bar, by placing your index and middle fingers on top of the brake lever you can reduce this physical reaction time by 0.15 seconds. That might not sound like much, but take a look at the graphs below:
The yellow bar is the physical reaction time and we’ve used a period of 0.62 seconds. At 60 kph, you will travel 16.67 meters a second. So if you reduce physical reaction time by 0.15 seconds you in turn reduce the distance traveled by 2.5 meters. Obviously at higher speeds the more distance you’ll save – if decelerating from a speed of 100 kph you would reduce your total stopping distance down by 4.16 meters. That’s a reduction of 5 per cent in stopping distance that costs you absolutely nothing in upgrades.
Going back to what we said at the outset about how some instructors have that said two fingered braking is dangerous. This comes from the fact that on some bikes, you need to pull in the brake lever almost all the way to the throttle bar. If you were to leave your ring and pinky fingers holding the throttle bar in such circumstances you wouldn’t be able to fully depress the brake lever and therefore wouldn’t be applying all brake pressure. That’s obviously bad, but it can easily be avoided by either adjusting your levers or if your stock levers don’t after adjustment, install ones that do.
Alternatively, don’t use two fingers, use all four of them. That’s why the term covered braking is also used. It’s not necessary to use the index and middle fingers only, it’s just what most people do because they find it comfortable. You could have all fingers wresting on top of the lever – the result is still the same reduction in your physical reaction time.
One other piece of advice is to have your fingers on top of the lever but not wrapped around it. For new riders especially, it’s all too easy to pull the brake lever in without rolling off the throttle – not a good situation to be in during an emergency braking procedure especially if the clutch isn’t pulled in.
Our recommendation is to use covered braking as much as possible, but it should be used without fail when riding in situations where you may need to stop suddenly, such as in heavy traffic. Given the distance saved, using two fingered braking might not just save you from a crash, it could save your life.