This video is sponsored by Skillshare - an online community where millions come together
to take the next step in their creative journey It’s a new year so what better time to dig
into new skills or get inspired by their expert driven classes.
I’ve used it both to expand skills I’ve already have some working knowledge in, like
infographic animation as well as discovering new areas like professional photo editing.
As it’s a brand new year, why not start with Thomas Frank’s Productivity Masterclass?
Learning individual skills is one thing but being able to manage your creativity and projects
is a whole talent in itself that will save you from a whole lot of stress.
Skillshare are offering you Chain Bear viewers two months free premium membership so you
can just binge classes to your heart’s desire for two whole months, for free.
Just go to the link in the description to get stuck in.
And now, the video.
Hello! Remember me? I took some time out for health reasons but it’s a new year so let’s
slide into things with a short and simple video about understeer and oversteer.
I’ve touched on these things before in the past and I think we most of us have a vague
idea of these concepts but let’s get everything straight in one standalone video. Easier to
focus on and look up later. OK so in track racing like Formula 1 when
the track turns, you ideally want your car to turn, too. A little insider secret there.
You definitely want to turn when the corner turns.
Not only that, you want your car to travel as fast as possible through the corner. I
know - it’s mind blowing stuff but bear with me on this.
So we’ve spoken about racing lines before, so for this corner here let’s assume you
want to drive this line through the track as fast as you can.
The way the car does this is through the tyres - the only part of the car that makes contact
with the track. The rear tyres are the driven tyres - the
engine pushes all the output power through the tyres and the rubber in turn pushes back
on the track to drive the car forward. So the car is being pushed onwards at the back,
via the rear tyres, in the direction the car is pointing.
The front tyres provide some very slight resistance when pointed straight ahead (just from friction
against the road), but when turned, they push sideways against the track which drags the
front of the car to the side. When working together with the rear of the
car being pushed forwards and the front of the car being pulled to the side, the car
will trace out a curved path, something like this.
At slow speeds, like when you drive a normal car on the road or something, this is all
pretty easy to control. You turn the wheels, the car turns and follows a path dictated
by how much you’ve turned the wheels. However when you’re trying to go as fast
as possible - as with all things motor racing - you reach the limits of traction and have
to toe a fine line. Let’s start with the front of the car. In
order to turn to the right, the rubber of the front wheels has to push against the surface
of the track. This is essentially the same mechanical setup as if you stood next to the
car in rubber-soled trainers and tried to push the car.
The car will resist behind dragged sideways as all physical objects prefer to be doing
what they were already doing and resist changes in momentum. If the resistance is too much,
you feet with slide on the floor as you can’t generate enough grip, enough traction, to
hoof the car to the right. This is the same as with the tyres. If the
car is going too fast for the corner, it has a lot of momentum in the forward direction
and will need a lot more traction to turn it through a tight corner. If the maximum
grip between the rubber and the track isn’t enough to handle that, the tyre will be dominated
by the forward force of the car and slide away from the ideal line.
This is understeer. You wanted the car to take a tighter turn than it could handle and
the car ended up turning in a more shallow curve. The front of the car lost grip and
didn’t have enough traction to turn in. Now to understand oversteer we need to move
to the back of the car, at the driven wheels. These wheels are being turned by the engine,
and can also be affected by whether or not the tyres and track have enough grip to handle
the traction demanded of them. They also work to make the back of the car
follow the front of the car through turns. The front wheels do the work of pulling the
car into the corner, but the back tyres then have to hang on, gripping the track to follow
the dictated path. There’s a lot of mass in the back of the
car, what with the power unit being back there and thus it carries a lot of momentum. The
inclination is for this mass to carry straight on and the rear tyres have to grip the road
to drag this mass in line. If the car is going too fast, faster than
the tyres can handle, the rear traction will exceed its limits and the rear will start
to slide away from the ideal line. This is oversteer.
So understeer is when the front tyres can’t hold on to the intended line and oversteer
is when the rear wheels can’t hang on to the intended line.
So fight back against understeer the driver might want to start steering a bit less to
give the tyres a turning angle they won’t slip against. It also helps to try and slow
the car down and come on the power a bit later. This results in a wider line out of the corner,
a slower speed. Oversteer can result in the car completely
spinning out of control. To counter the back end sliding out the driver will want to drop
the power and steer out of the corner. This should help bring the front end back in line
with the trajectory of the car and straighten it up. As with understeer the result can be
a reduction in speed and a wider path through the corner than intended. But, if you saved
if, at least you didn’t crash. The fastest way through a corner is just on
the limits of how much power your tyres can handle. Finding that and holding that through
all manner of corners and conditions is what might separate you from the rest.
Now you may ask, what about rally cars. Especially the old rear wheel drive cars - those things
were sliding through every corner - that’s oversteer right? How is that the fastest way?
Well, rallying is a different beast that I won’t go into detail here. But rally surfaces
are often a lot less grippy than race tracks - dirt, mud, gravel, snow - very slippery
stuff and tricky to generate traction. In these cases, it can be faster to hang on
to momentum and slingshot sideways through a corner. How does this work?
Well if you imagine a car sliding through a corner. As the car is pointed inwards, you
can use the driving force of the car to push the car into the apex, tighter into the corner.
So the car’s momentum wants to go onward but the driven wheels are pushing it inwards.
You don’t see F1 cars doing this in the rain as the way they are weighted and sprung
means they are much more on a knife edge when it comes to spinning. You can hold the slide
on a rally car but F1 cars really want to snap much more easily on you. Plus the tyres
are not designed to be sliding against the surface so you’ll knacker them too. That’s
the difference!