To be able to obtain the best performance from the tires is
fundmental to be winner in all the categories of the motorsport, and
the kart in this doesn't exception!
The aspects that affect the performance of the kart tire are
pressure and temperature.
The pressure in fact affects the footprint that the tire offers
depending from the load to which it is subject, while the
temperature affects the level of adhesion that the tire compound
generates on the ground.
The temperature that the tire reaches depends from the loads to
which it is subjected, from the grip that the tire itself is able to
supply, and from the air and ground temperatures, therefore on a
certain track with certain atmospheric and grip conditions, the
level of the temperature that each wheel reaches is consequently
Acting on the setup of the chassis of the kart however you can
change, even if slightly, the loads acting on the wheels, and also
sli angle and slip ratio of the tire, so to work on the setup of the
kart is the only way to change the temperatures that the tires
However in kart the compounds used are not as sensitive to
temperatures as it happens for the tires of other categories of
motorsport (formula 1, motogp, etc.), therefore the window of
temperatures with which the kart tire offers a good level of grip is
enough wide, so the temperatures that the tire reaches are not so
important for maximum adhesion.
The pressure of the kart tire, on the other hand, is obviously
linked to the cold inflation pressure of the tire, and then
increases during the laps in function of the tire temperature.
On the pressure of the kart tire you can therefore intervene
directly by modifying the initial inflation pressure, so let's
understand on what bases its value should be defined to get the
maximum efficiency of the tire lap after lap.
HOW TO MODIFY THE PRESSURE OF THE KART TIRES
As we have seen, the pressure influences the tire footprint in
function to the load on the wheel, so the value of the pressure that
must be used is primarily linked to the weight of the kart, to its
balancing, and to the load transfer that there is under braking,
acceleration and corner.
So depending on the characteristics of the kart, of the track and of
the ground conditions, on each wheel, at each point of the track,
there will be a different load, so ideally the pressure should
change continuously to allow the tire to always have the maximum
performance, of course this it is not possible, but it is possible
to identify the pressure that each tire must have in relation to the
average load acting on each wheel during the lap, and which
consequently guarantees averagely the maximum footprint and grip at
each point of the track.
It is therefore clear that for each track, and for each grip
condition, it is necessary to use different pressures to get the
maximum performance from the tire, but the discussion does not end
here, so far we have talked about the cold pressures that allows the
maximum performance of the tire in function of the loads to which it
is subjected, but lap by lap the pressures change due to the
increase in temperature of each wheel, so the situation that was
initially optimal is modified, and therefore this aspect must also
be taken into account.
For example, in the kart world in a completely empirical way the
mechanics to compensate the increase of temperature and therefore of
pressure are used to keep at a lower pressure the tires that at the
end of the run have recorded a higher temperature, but this allows
to take account only of a part of the problem, in fact if the tires
have a higher temperature is also because they are more loaded, then
instead to be deflated, they should be more inflated to offer the
maximum footprint on the ground, so the result is that for all the
first laps the tire works badly, and only after that the temperature
increasing has returned the pressure to the right values, the tire
begin work properly.
As you can see the variables involved are many, and often they are
in opposition, therefore to work only with the experience, or to use
more or less correct empirical methods, it is not sufficient to find
the optimal pressures to be used in the differents situations, but
it is necessary to take advantage of the help of tools and software
that allow to find the optimal compromise each time not only in
function of the characteristics of the track, and of the atmospheric
and ground conditions, but also in relation to the number of laps
that you must carry out.
Continuing the reading you can start thinking of putting a important step for the growth technique of your team and of your job.