Advanced Braking can Gain You
a Few Tenths......PER CORNER!
Warning:
This is the sort of stuff I get into with drivers after I've done
everything I can with normal coaching. If you are still
a relative novice or are looking for seconds a lap please read
my other braking
articles first. You will need 100% confidence whilst braking
for this tutorial, so that all your mental energy is free to make
the subtle driving adjustments necessary to make this work.
How to find a tenth of a second with
braking technique into sharp bends
Right, we analysed a lot of data collected using AiM
data acquisition to study the fastest way round the hairpin
at the end of the long straight at Whilton Mill. Our
driver, who on the day was hitting laps close to the lap record,
approached the corner using different braking techniques. One
technique in particular was a tenth quicker than the rest. I'll
spell it out to you here step by step so you can do it yourself.
We tested the following techniques in as many combinations
as possible, to find the ultimate way through that sector of race
track
- Early braking for faster exit
- Late braking for fast entry
- Hard braking with locking rear wheels
- Soft braking with zero locking
- Medium braking with semi lock
- Release brake pressure fully before turn in
- Carry braking deep into corner
Here is the combination that worked best, its very very tricky
to do, but was worth a tenth on one corner compared to
other very effective techniques, which is worth a hell of a lot
of money at this level!
You can see more tests we did to get to our ultimate braking
technique on my kart
data acquisition site.
Step one – Braking Point
The ideal braking point was found by our driver using the latest
braking point he could manage without missing his apex, and then
braking 1 or 2 metres earlier than that. That's what I mean by
breaking slightly early
Step Two - Braking Pressure and Release
This is difficult to consistently achieve, but your braking sensitivity
will increase steadily with practice. It's also pretty difficult
to describe so I'll show you how different braking techniques
show up on our data, and hopefully it will be clear how you can
replicate the technique.
The red line shows how the axle speed has much more drastically
dropped below the GPS speed ie the actual speed of the kart. This
shows a much higher degree of sliding under braking for the red
line which under braking is still pretty effective. I've also
popped in an example of an even higher degree of lock up in yellow.
That's the sort of lock up that produces a strong kick at the
rear of your kart.
Now, the yellow and red lines both slow the kart down
very effectively, and you can even say the yellow 'big lock up'
slows the kart even better than the others. However,
the least aggressive of the 3 braking techniques gets all its
time back when it comes to releasing the braking pressure and
carrying speed through the corner.
With the more aggressive braking shown in yellow and
red, the kart tends to be less predictable when it comes to releasing
the brake pressure and persuading the kart to enter the corner.
Sometimes it will snap back a little as the kart straightens whilst
you release the brake, or as you try to start turning you might
marginally overload the rear tyres and feel like the kart isnt
happy to turn, so you continue to lose speed until you feel like
the kart is back with you. The idea is that its difficult to bring
the rear wheels from a heavy lock up situation, smoothly back
to turning at a rate that matches the road speed of the kart,
which is when they are ready to give you maximum cornering grip,
and a feeling the kart is ready to turn in.
When as in the example of the green line, your braking
wheels are turning at a speed closer to the speed of the kart,
its easier to bring those wheels to match the speed of the kart
(by releasing braking pressure), giving you maximum cornering
power and most important.. a feeling that the kart is ready to
turn and carry that bit more speed. You still have to
have a slight locking of the rear tyres, enough that you can hear
the rubber biting a squeaking, but the more you develop feel for
the right amount of lock that you can control with subtlety, the
more cornering speed you will carry.
Step Three - Throttle
Studying the throttle trace held a bit of a surprise.
On first inspection you can see that the red line which
is the slower of the two, gets onto the throttle earlier. The
quicker green line gets on the throttle slightly later but reaches
maximum slightly earlier. Now, so they say – the guy who
gets on the throttle earlier is quicker..... not wholly true,
which is confirmed in a throttle
position article on my data acquisition site
This is because on the slower lap the driver was anxious
to get back on the throttle early because he was aware that he
had lost some cornering speed at the apex, and in trying to get
it back he pushes a bit too hard and the rear tyres give up a
little. You can see on the slip trace that the red line
is higher than the green, revealing a slight amount of wheel-spin.
The feeling of slight traction loss caused our driver to hesitate
a bit on throttle application which cost a bit more time.
We've gone through a similar
process at every corner at Whilton Mill, and our data has revealed
that we should find another half second at least, so we expect
our pace to be significantly below the lap record next time out.
I'll let you know how it goes!!
If you want to find time easily like this, you can plug in the
AiM
GPS straight into the Mychron 4 and get started immediately.
For me getting into data has been a revelation, and for
you it will increase your understanding of driving to such degree
it may well blow your mind, so consider this a health warning!!
And for any budding career drivers, you need to be able to talk
'data acquisition' fluently. So I strongly recommend you get into
it. In fact, for me it seems like a crime not to run data on your
kart, because every single lap you run can find you tenths which
can only be revealed by data... you could be throwing away seconds!!
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