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BRAKING
techniques
Although brakes are the most important active safety device on
our cars, they are often overlooked as a source of huge driving
excitement and enjoyment. Here are a few techniques to help you
get the most out of your car's brakes, and enhance your level
of driving enjoyment.
Most of us who love driving on our favourite bit of road are
willing to find out how hard our cars will corner or accelerate
before things get interesting. But how many of us are really aware
of how our car behaves under extreme braking? The idea of braking
during hard driving is to slow down the car as quickly as possible,
and with a high degree of precision, so we are at the perfect
position and speed for a particular corner. It is wicked fun hauling
down a car with powerful brakes; you can feel the chassis squirming
underneath, as you try to brake as hard as possible without locking
up a wheel. Brilliant.
threshold braking
This technique is simple: brake as hard as
possible without locking up a wheel (a.k.a. skidding). This
works by quickly and firmly squeezing the bake pedal until you
start to feel the car squirm under you, and the tyres are at the
point of losing their grip. The point at which you start to feel
one or more of your wheels lock up is the threshold of grip. Once
that happens, the goal is to stay right on the limit of braking
grip, without locking up a wheel, until you reach the desired
entry speed for a corner.
Almost all modern cars now have anti-lock braking systems (ABS),
which are basically designed to perform threshold braking for
you, but some sports cars do allow you to have a bit of fun before
the system steps in.
cadence braking
Like threshold braking, the idea is to keep
the wheels from losing grip, but works in situations where the
limit of grip is harder to maintain (such as wet roads,
or broken surfaces like gravel) or the whole car starts to become
unstable. With cadence braking, each time the wheels lock up or
you begin to lose stability, you quickly release the brake and
then re-apply it once you regain control. In low-grip conditions,
you will probably find yourself repeating this process several
times before you can slow down sufficiently.
This technique obviously has to be performed very quickly in
order to slow the car down as fast as possible, and you need to
be very sensitive with your braking foot to be able to apply just
the right amount of pedal pressure, and read the telltale signs
of a locked wheel.
Cadence braking can sometimes be used to rescue
you from a bend gone horribly wrong: by sacrificing your cornering
line, you can shed a lot of speed if you went into a corner too
fast. This involves quickly - and very carefully - alternating
between straight-line braking and cornering, and can save you
the indignity of punching a car-shaped hole through the roadside
hedges.
brake fade
While there is nothing like a bit of enthusiastic
hard charging - or hard braking - most road-going cars have brakes
that were designed only for a few very hard, sustained stops.
After those, the build-up of heat from that extreme braking causes
the brake fluid to literally boil, and a huge drop in braking
performance quickly follows. This is commonly called brake
fade.
Obviously, different cars will have brakes with different performance
limits, but if you are going to do a bit of committed driving,
always make sure you have enough lining on your brake pads, and
always be aware of how the brake pedal feels during your drive;
if it starts to go mushy under your foot during hard stops, it's
time to slow things right down and give the brakes a while to
gradually cool. If you stop driving immediately after a hard charge,
don't apply the handbrake either. Give the rear brakes a
chance to cool down first, or you may not be able to release your
handbrake when you're ready to move off again!
braking into a corner
As mentioned before, the objective of braking is to bring the
car down to the ideal speed, so you can carry the most speed possible
into, through and out of that corner.
Most drivers will agree that the best way to brake
for a bend is as follows:
- Line up your braking point; it is the spot on the road where
you have determined you need to start braking in order to bring
the car down to cornering speed.
- Once you hit your braking point, quickly and firmly squeeze
- don't suddenly stab - the brake pedal so that you are braking
in a straight, stable line.
- As you reach the turn-in point, smoothly release the brakes
(to get the car nicely settled for the task of cornering) and
then begin to turn in to the corner.
Depending on the car and/or the driver, it's
even possible to still be braking while turning into
the corner (known as trail-braking). This has some performance
advantages, but also the added risk of reduced overall stability
and driver control if things go slightly wrong; a tyre's level
of grip is like a person's level of concentration. Every new task
you heap on them means there is less concentration available for
the tasks before. It's no different for tyres. Once you turn in
to a corner while still on the brakes, you begin to sacrifice
overall braking grip (meaning you could end up spearing into the
corner too fast) and your overall cornering grip will also be
hugely reduced, compounding your cornering problem even more.
Once you learn to master braking on the limit, and you are fully
aware of how your car performs under heavy braking, you can become
even faster and far safer behind the wheel, and you will add yet
another hugely enjoyable element to the driving experience.
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