Dynamic ESA: What is it…? How does it work…?
What does it do…? And how does it interface or interact with the rest of the systems
on our BMW? And there are a lot of systems, including all the different sensors. And we mustn't
forget the IMU, the Inertial Measurement Unit. On the 2021 onwards GS we've got a six axis
IMU, and it plays a vital role in creating the algorithms and the profiles, that BMW generate to
control our suspension. So we've got a lot to cover. But most importantly: handlebar controls.
This is the question, I'm most often asked. On the right hand side we've got riding modes, on
the left-hand side we've got our suspension adjustment. What do all these buttons do?
So at the end of this video you are going to have a better understanding of how everything works,
how it all interacts and interfaces with each other and what these buttons do and most importantly,
how you can get the best from your bike.
Now this just happens to be a GS, but this episode is going
to apply to a lot of BMWs – anything with Dynamic ESA. The principles are the same. So we need
to get started. But you just need to remember, this episode is about suspension. There is going
to be a separate second episode, and we're going to cover all the riding modes. So these two
things I'm going to keep separate: Dynamic ESA is now today, and the next episode is about Riding
Modes. They are connected, but I'm going to keep them separate to make it easier to explain.
So let's get started. – So hello and welcome. My name is Carl. The channel is called "Just The
Way It Is", and we're talking about Dynamic ESA. So where do we start? Well, the single most important
place to start is the rear suspension and pre-load. But first we need to go back in time a little bit.
Originally with the older bikes without electronic suspension, the most important thing to
set up on your bike has always been and still is the preload on the rear.
Now, a lot of people will
talk about bike sag and rider sag. And that is true. But just for talking about it today, we want to
stick with just one term, which is rider sag, which is the weight of the motorcycle plus the
rider in the normal riding gear. And it's important, we understand, that there are times, when we would
look at bike sag separate to the the weight of the rider and the bike, but we don't need to
talk about that today, because it's just going to confuse things for you. So if you can imagine
(I've made this up to make this easier to explain)… If you imagine, this is a coil spring.
On the GS,
on the standard GS we have approximately 200 mm of suspension travel measured from
the axle. So if you imagine, this is the coil spring, it is generally accepted, if you're setting
up sag – which is the weight of the motorcycle plus the rider in his normal riding gear – when you
set that up, you should be at the end of the first third. So this is the complete travel
of the spring, and then if I turn this around, I've split this into thirds, so we've got the
upper third, the middle third and the lower third. So it is generally understood, that what you
should do is, when the bike is uncompressed, in other words: if you were to jack the bike up,
and the wheels were completely off the road, there would still be a very small amount of tension,
pressure on the spring, so it doesn't rattle around. Then you lower the bike onto
the ground, no rider at this point, just the weight of the bike, and then that spring, if you watch
this yellow marker here, that spring compresses a little bit, and then you add on the weight
of the rider in his or her normal riding gear. And then what should happen in an ideal world
is (watch this yellow marker), it should move to approximately the top of the second or the
middle third of the movement of the spring. And this is the ideal place for the spring to work.
So you're sitting on the bike in all of your normal riding gear, and the spring should work in
this zone here.
This is where it should be working, we have a button, that controls preload, rear spring
preload. So we're going to start at the bottom. So there are three settings: there's Minimum, there's
Maximum and there's Auto. Let me explain all three. Now, Minimum is is – if we go back to that spring
again – that means, that the spring is pre-loaded with weight at its minimum amount, so that the
back of the bike is really soft and spongy, and actually the back of the bike
sits quite lower to the ground than any of the other two modes. Now, initially I thought:
what use would the Minimum setting be? Now, it actually is a really nice setting, and it comes in really
handy.
So you might like to spend some time getting used to how you turn that from Auto
to Minimum, and how you make the most of it. So with the engine running, we press the shock
absorber symbol on the left hand handlebar once. And once we bring the screen up, we can see both
options. But we want this screen on the right hand side. So to access this, we have to have a
long press. Long press is going to change from Minimum to Auto. It confirms it's changed to Auto.
If we want to change that again, we press once, followed by a long press. And this time it
changes from Auto to Maximum and confirms our choice to Maximum. One more time: short press
followed by a long press will then allow us to go from Maximum back to Minimum again. So just to
give you some examples, that I actually use it for: In the summer my bike's in the garage or
all our bikes are kept up in this garage, but in winter I move them from the garage to
the cellar.
But to do that, I have to go through the garden. I have to go through a path, and I
have to go up about 2 m in height, and I use scaffolding poles and planks of wood
to get the bikes from the garden into the lower cellar, where it's about 12 degrees during
winter. But to do that, it's quite nerve-wracking, because the bike's quite high.
But if you change
the pre-load setting to Minimum, the back of the bike drops down quite considerably, and you can
get your feet well and truly firmly planted on the floor. So that's the first time, I use it. And
I thought, actually this is really quite good. The second example, I can give you, is:
if you've got a pillion or a passenger, that's quite short in height, and they find it
quite a step up to get onto the rear of the bike, you can use the Minimum setting to lower the bike,
so that they get on, and then return it to the mode you want afterwards.
So in other words, if
you imagine, this is the bike the back (I'm going to over exaggerate), the back of the bike lowers, your
pillion can get back on again, you reset it, and off you go. So the times, that I've used that, and
it's actually come in very handy, is petrol stations. Normally, if you're stopping for petrol on
a tour, you've been out for quite some time, you might be getting tired, and it's time for a
break for both, you and the passenger, so when you pull into the petrol station forecourt (you
need to remember: for this function to work, the bike needs to be in Neutral, and the engine
needs to be running), and then you change the setting on the left hand handlebar from whichever
one you have it in, which would then be either Auto or Maximum, and you change it to Minimum, and
you just have to give it just a couple of moments, and you can start to feel that bike drop down.
Now,
from the rider's perspective, you can feel quite a difference, but from the pillion perspective,
because they're further back on the bike, it is a huge drop, compared to what you feel sitting
here. So all I can tell you is: it makes life for pillions much easier getting on and getting off.
So if your wife or your partner is quite short in the leg department, use the Minimum setting.
It's really good. The only thing, you have to be aware of, is the way BMW have got it set up is, when you then
change it back from Minimum to Auto, it takes some time to self-adjust. So for example, you've pulled
into the petrol station, you put the bike in Neutral, the engine's running, you've gone from Auto
to Minimum, the back of the bike has dropped down, your partner's got off or your pillion's got off,
then you filled up with fuel, you start the bike up, you get on, your pillion gets on, and then you
change that setting again from Minimum to Auto, it will take several minutes of riding on the road
for that suspension to level out.
So when you first pull out at the petrol station or from the
forecourt, the back of the bike or the whole bike actually is going to feel very soft and spongy.
Don't worry at this point, there's nothing wrong. That's the way it's going to work. And just so you know,
it takes even longer to go from either of those two settings to Auto, the colder it gets.
In winter I actually thought, I had a problem with the bike, because I couldn't get it to go
from Minimum to the Auto level, and I waited 5 minutes, and basically nothing had happened,
but that was 0 degrees.
It was really pretty cold, and if you read the BMW manual, they do tell you
in the small print, that it takes some time, and it takes even longer, when it's cold. So just
to confirm: when you're changing from Maximum to Minimum, it happens really quick, no problems. When
you're going from Minimum to Maximum, it happens really quick. And what I'll do is, I'll put
up a clip right now, so you can see it working. So currently we're in Auto mode. So what
I'm going to do now, is change it to Maximum. So now I've changed it to Maximum, and look, it's pushing down the top of the spring, and
it's increasing this gap between these surfaces. So now it's finished. So the spring is now under
its Maximum preload. What we're going to do next is, we're going to change it from Maximum
to Minimum, so you can see what happens. So now we've changed the setting to Minimum,
and you'll see that the actuator, the stepper motor inside here is reducing the pressure
on the spring and reducing this gap, and it will reduce it to its absolute minimum.
Now, what
we're going to do next is, we're going to return it back to Auto mode, but what you'll notice is,
that the spring does not compress, in other words: the spring preload does not automatically bring it
halfway between these two extremes, and the only way the bike determines, where the Auto limit is
is, you have to ride it. So let's just have a look: So now I've changed the setting to Auto, and what
should be happening is, this should be compressing, but it doesn't, and it will only do this once
the bike is on the road, once you're sitting on the bike.
But if you're going from either of those
extremes to the Auto level, the bike only makes those adjustments once you're on the road. So you
have to wait to get moving. And depending on the temperature, depends how cold or how warm it is,
it may take several minutes of riding, before the bike self levels. So that's the minimum setting. So the
next second setting, we need to talk about, is the Auto setting. So if we go back a little bit to the
beginning, when I explained, on the 2018 bikes you had solo, solo plus luggage and rider plus
pillion. They were your three options. The way to think of Auto on the 2021 onwards bikes is,
this setting replaces completely these three settings. That's what the Auto does. And we now have height
measuring devices front and rear on the bike to determine, how high or how much the
suspension is compressed. So when you choose on the left hand handlebar the Auto mode, it's sort
of like you could call it self-levelling. It's not quite self-levelling, because there's no self-levelling
on the front, it's only the rear.
But it does a very, very good job. And for the vast majority of the
time, including myself here, Auto is the mode to be in. Now the really clever thing, the thing, that
makes the difference, is this Auto levelling mode. So if we go back to that spring, and we go back to… In
an ideal world, at a suspension specialist, he would set your bike up, so that, when you and all of your
gear and all of your normal riding luggage are on the bike, and you sit on the bike ready
to pull away, your spring would have compressed to the top of the start of the second third, which
is this middle bit here. Now, what the BMW engineers have done with the auto levelling is, the bike will
automatically go to this point here, regardless of how much additional weight you put
on the back.
So if it's just you, it'll find its place. But it takes a few minutes of riding to
find this actual place. If it's you plus luggage, normally the bike would compress a bit more, but
it will then self-level and come back to this top of this second third. And if it's you plus
a pillion plus all your luggage and your top box and side boxes, again, it will compress
initially even more, and then it will come back and find this perfect starting point right here. So the
Auto does a very good job of determining, where the pre-load level should be for maximum use of
the spring. And that's the mode, in terms of the spring preload mode, that I use
the most, and that's probably the mode, you should start in. Now, the next one is called Maximum. So
why is it there and when would you use it? Well, if you're an off-road rider, you need as much
suspension travel, suspension clearance in terms of ground clearance, as you can possibly get. So you
would be well advised to jack the back of the bike up, which means changing the spring preload setting
from Auto to Max.
And if you do that, again we've watched that video, and you can see, how much
that spring is compressed, the back of the bike comes up an awfully long way. So that's its first
application, which is for using the bike off-road. But there is another application.
For those of you, that are a bit more of a sporty rider, I did an episode all about the R1250R, and I had three of them.
I had one of them for a month on loan from BMW, beautiful bike. And I found, that in terms
of the suspension setting for that bike, the way the bike handled the best, was to change
the spring pre-load setting not on Minimum, not on Auto, but on Maximum, in other words: it would take
the back (I'm going to over exaggerate), the back of the bike would then come up quite some way, and
that affects the rake and the trail, in other words: the suspension angles on the front of the bike.
And
it makes the bike steer much quicker. So you might like to have a play with that, and it's going to
take you some time to feel the difference. The bike will feel quite weird, because your feet will start
to come off the floor, and you'll be on the balls of your feet, because the back of the bike does
come up quite a bit. But that's another time, that you can use Maximum, if it's just you, and you want
some really sporty riding. If the roads are smooth, that's something to play with. If the roads are
awful and full of potholes, you don't want to use it. The back of the bike will bounce around and
crash around, it's just not a pleasant experience. So when else would you use Maximum?
Well, maximum also comes in, if you are a big guy. If you're in that 120-130 kilo range, and
you take a pillion on the back, that is a lot of weight. The bike still handles it, don't worry, but
you might like to try riding the bike with that spring preload set to Max.
So it might make
it a bit more awkward to get on and off the bike, but in terms of levelling the suspension out,
the Auto setting can only do so much. If you're a big heavy guy, try experimenting with the
Maximum setting. So I think, we've covered the essentials for the spring preload. My advice
is to ride with it in Auto for the vast majority of the time. One up or two up, Auto does a very good
job of pre-tensioning that spring, so it's at the start of this middle third, where it does all of
its work. As to the Dynamic ESA bikes, that's all of them from the R1250R, the RT, the GS, the S1000R and
the RR, when you change those spring preload settings on your left hand handlebar, the computer
automatically changes the damping settings. It doesn't let you see that, it doesn't tell you,
what it changes, but it does make a change, because as soon as you add a preload to a spring, in other
words: when you take that spring, and you start to compress it, you must increase the rebound damping,
in other words: the rate or the speed, at which the spring rebounds, after it's been compressed.
So if the bike goes into a dip in the road, it extends first of all, which is the rebound,
so in other words: the tyres following along, and it goes down a dip, actually the suspension
uncompresses in that initial movement, and that is the rebound, and so it's important, that
they control it.
So in each of those settings, that's Minimum, Auto and Maximum, the computer
also makes a change to the damping settings on the rear shock, so you do not need to go in
and change your damping settings. At this point ujt leave it alone. So the first thing to do with
your new BMW, that's got Dynamic ESA, is have a play with the spring preload button. Don't play
with anything else, leave the bike in terms of riding mode, leave it in road, leave the
damping button in road, and just have a play with the spring preload.
This is the first thing, and
this is the most important thing to get right and to understand: what happens with the
spring and just find the one, that you find is most comfortable to you. So let's move on.
We now need to talk about the damping settings..