If you are reading this, it is assumed that you have passed your riding test and can handle a big bike competently, able to ride it as second nature. The information in here is to help you negotiate corners better since going down the straight flat-out should not be too much of a problem.
Those who have never seen a highly-trained rider at close range (especially if they are overtaking you) negotiating a corner would likely be staggered at what they can do (it looks much slower on TV). Common comments are “They are so brave” “Balls of Steel” etc. etc. Whilst most of them would probably be flattered by the compliments, in honesty they would probably tell you that bravery had very little to do with it.
Why? Bravery means doing something despite being afraid of a likely outcome, in this case an accident. But a good rider will happily take the same corner at the same speed 20 times without any problem at all. He knows what his outcome is, and crashing is not one of them. Therefore, bravery has very little to do with it, more ability. He knows he is riding well within his skill level.
If he can do it, so can you; maybe not to the 0.1 sec as him but certainly within the same ballpark. After all, he has very similar reflexes, eyesight etc. The only difference is training, knowledge, experience and will. This is important to appreciate- even Rossi is a human being, with all the limitations of one. What makes him so different to you? This something is very largely attainable with the right attitude.
Much of the information here is counter-intuitive, i.e., it goes against what many would consider instinct whilst riding. If you are new to this, take your time assimilating and learning it doing so at a pace which you feel confident. Confidence and commitment are the keys for good safe riding and these only come once you have a high degree of certainty in what will happen next to every one of your inputs to the bike controls.
Riding Around a Track is an extreme exercise in time management. I’m assuming that your goal is to negotiate the track as quickly as you can. During this time, between gearchanges, changes of direction, throttle control, choosing lines, braking etc., the workload can seem overwhelming. We can all do many things at once, but to get round a track quickly, it is best to give ourselves time to do these things one at a time, distributing the tasks as evenly as possible and not trying to perform them all at one time.
A Motorcycle is Inherently Stable
Any bike handles well. At standstill, the suspension is stable, the bike is not moving- it is fine. The problem comes when a rider climbs on and attempts to make it do things without fully comprehending its dynamics and how it will respond to different inputs. Realize that many of your actions aboard a bike are unsettling and destabilizing, and it will be easier to understand what it will do next.
Steering Counter-steering & Gyroscopic Forces
“A body at rest will remain at rest and a body in motion will continue in that motion unless acted on by an external force”– Newton’s laws of motion. A motorcycle moving at speed (say 100kmh) will move in a straight line and continue to do so unless something forces it to change direction, in this case, you.
This is important to understand, because it is a combination of this and gyroscopic forces acting on the front wheel (see diagram on gyroscopic forces below) that are responsible for a very strange effect called Counter-Steering. When traveling at speed, turning the handle bars of the bike will cause the bike to bank in the opposite direction (trying to continue in the same direction), i.e. pushing the left handlebar to will cause the bike to bank to the left. It is contrary to what we experienced when riding a bicycle and has caused a great deal of confusion among riders until the phenomenon was understood.
Try it (carefully) the next time you are riding your bike. Whilst the bike is upright at a good speed (say 80-100kmh) push the left handle bar. Which way does the bike bank? Common sense will tell you that the bike will turn right, experience will tell you otherwise. Understanding this will allow you to get the bike to negotiate a turn quickly and predictably; you are approaching a left-hand corner, it looks sharp, just using bodyweight shifting is never going to get you to turn quickly enough. Push the left handle-bar and the bike will bank left, setting you up to take the corner.
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WEIGHT DISTRIBUTION
The key to riding a bike well is to realize about weight distribution and how it can be changed. Most bikes have a weight distribution of around 50:50 front to rear, but put a rider on, accelerating and braking and this can change wildly from 100:0 (very hard braking) to 0:100 (pulling a wheelie). A rider can affect weight distribution to some degree by moving his body backward and forward but the control which has the most influence over this is the throttle.
In a corner, think of the throttle as the weight distribution control.
Most bikes have a larger rear tire than the front with a tire contact patch ratio of about 40:60 front to rear i.e. the front tire has 40% of available grip and the rear 60%.
Therefore to achieve maximum corner speed, the bike needs to be using all the available grip by putting 60% of the weight on the rear wheel and 40% on the front wheel. How is this done? The same way a wheelie is done, by accelerating, i.e. rolling on the throttle. Throttle controls the weight distribution.
Again, this is counter-intuitive. Common-sense tells you to slow down into a corner, physics tells you to speed up. But it is important to note that this approach will only work if you have room to accelerate, i.e. you are not going into a corner too fast.
There is another reason to roll on the throttle when cornering: because of bike geometry, when power is applied, the rear suspension will extend, i.e. the rear will rise. Again this is counter-intuitive and most people whom have not been shown otherwise, will assume (incorrectly) that the rear will squat. When the rear rises, the effect on the front suspension is to make the steering head angle steeper, which will cause the steering to sharpen up. The net effect is to make the bike track the corner better. Please see the diagrams below:
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Conversely, not applying the throttle when in a turn will do the opposite and cause the bike to feel less able to turn.
Make sure that you have the correct speed before you even start the corner, gearchanges done, braking finished and once banked over, roll on the throttle gently to shift weight to the tire that has the most grip- the rear. The earlier this is done, the quicker you will get around the corner and the more stable you will be. This does not mean applying maximum throttle and hanging on but a gentle roll-on the throttle to change the bike from weight forward due to slowing down (most weight on front tire) to gentle acceleration (majority of weight on rear tire). Of course, shift your body weight front to rear accordingly to help with this effect.
The most common cause of accidents is to go into a corner too fast, think, “Oh S@#t!” and close the throttle. The bike would most likely have made it around the corner until the rider closed the throttle abruptly, sending most of the weight to the front tire which had to deal with turning forces, and then all of a sudden, braking forces too. At best, the bike would stand up (many bikes will stand up from a banking attitude under braking) and go straight off the track. At worst, the front end would slide and a low-side follow. The best course of action here (counter-instinctive) would have been to roll on the throttle and take the corner. Instead, the instinct for self-preservation caused a crash.
Because of this, until you are confident and consistent with your corner entry speed, keep it within your own confidence levels and learn to apply throttle as early as possible through the turn.
It almost goes without saying therefore, that to achieve this, every other action, such as gearchanges, braking, hanging off must be completed before you even begin to bank the bike for a turn.
This concept is discussed very thoroughly in “A Twist of the Wrist Vol 2” by Keith Code. Read it for further elaboration on this topic.
YOU GO WHERE YOU LOOK
Human beings were not designed to go 120mph. They were designed to max out at less than 20mph. This does not mean we cannot safely go at these speeds, it simply means that we are not able to use our built-in protection systems because they are operating way out of their normal operating parameters. We have to make a new set of instincts for ourselves and this takes training.
Normal human reaction times are approximately 0.4 – 0.6 seconds. I.e. it will take half a second to realize that an event has happened. Decision time can be 1-2 seconds and action anywhere between 1-4 seconds. This means we need to be aware of what is going to happen in the next 2-3 seconds in order to take appropriate action in time. At 5kmh, this means we have to look 1.5 metres (5 feet) ahead of us and generally, people walking will only look this far ahead. Doing so at 100kmh would give an impossibly small reaction time. At 100kmh this distance should be at least 30m (100ft) and at 150kmh this should be at least 50m (160ft).
This apparently simple task causes a lot of difficulty for many riders. Riding with your attention focused at too close a distance will give more erratic lines, rougher inputs into your controls instead of smooth inputs (this will destabilize the bike) and unnecessarily slow you down without any increase in your riding safety.
Looking farther ahead will help you to smooth your inputs to the bike because you have more reaction time. This will help you relax which is the key to going faster.
You know that you are riding well when your lap times decrease but you feel like you are going slower. Smoothness pays huge dividends in every aspect as it allows you to have a greater margin of safety or higher limits- you choose.
Having established that you need to look further ahead, than might at first be instinctive, may not be a problem on the straights. But what about around the corners? The temptation here is even stronger to look just in front, to look where the bike is pointing, forgetting that the bike is only pointing there temporarily and will not end up there. You should be looking where you aim to end up. A corner should be taken in one turn, not lots of little ones, and the only way to achieve this consistently is to look much farther into the turn then instinct tells you. This will make finding the right line much easier, cause far fewer corrections to the line, hence better throttle control (less variations to upset the bike and keep it within safe parameters)
For confirmation of this, look at where GP riders heads are pointing when they are hanging off the bike in a turn; it’s not straight ahead of the bike but between 30º - 45º off-centre from the straight ahead, depending on the radius of the turn.
There is another reason for this:- on a bike, you go where you look. This is why an accident at a race often doesn’t involve one bike. Human instinct is to look at the unusual event for danger, thus being attracted to it. Instinct on a bike is not a reliable indicator to trust until a new set have been created from training.
Hanging Off
Hanging off is a useful way of lowering the bike’s centre of gravity and moving it towards the centre of a turn whilst turning. Doing so allows cornering at a higher speed for the same angle of lean. Tyre geometry places limits on how far a bike can lean over, limiting the speed at which a corner can be taken maintaining balance. Hanging off can increase this.
However, the action of moving to a hanging off position can destabilize a bike so make sure that you are hanging off before you bank the bike over to negotiate a turn.
Braking:
Smoothness is the key to effective braking. Before maximum braking can be achieved, the front suspension needs to be set up. This is done by applying enough front brakes to compress the forks without taking them to their stops. Doing so will cause the front tire to lock or skip because there is no further wheel travel. If the front tire locks, most of the braking will be lost and the bike will be in a skid. Instincts will at this point instruct the right hand to apply more brakes since all retardation has been lost. This is exactly the wrong input. Unlocking the front wheel is done by releasing the front brake enough to allow the front wheel to regain traction and begin turning again and then to smoothly reapply them without locking them again.
During hard breaking the majority if not all weight is transferred to the front wheel. Very little if any weight remains on the rear wheel. It is for this reason that 80-90% of a bike’s braking power is at the front wheel. It is mostly not necessary to use the rear brake for maximum braking since engine breaking from gearchanges will already be causing the rear wheel to be close to its traction limit. The rear brake can be used to “top up” a little at the rear wheel once the engine speed has come down, reducing engine braking.
Because hard braking will take the front tire to its traction limit hard braking should be done whilst the bike is still upright and no cornering force is required of the front wheel. Once the bike is in a turn and most of the grip of the front wheel is devoted to turning the bike, little is left for braking. For this reason, braking should be done before entering a corner.
Advanced technique: release the brakes gradually as the bike is banked into the turn. The timing of the release of brakes should be 100% when the bike is upright to 0% once the bike is fully leaned over. This is difficult to do correctly and should only be attempted once the rider is very comfortable with late braking.
The reasoning behind this technique is to minimize suspension movement before the turn. At full braking when the bike is upright the forks will be almost fully compressed. Releasing the brakes will cause the forks to rebound. Going into the corner will again increase the load on the forks causing them to compress again. This see-sawing action on the bike will destabilize the bike with unwanted consequences. Using the above technique will help smoothen if not eliminate these oscillations.
To maximize braking, the torso should be straightened to the upright position and the bum moved as far back as possible. This adds wind resistance to help braking and moves the centre of gravity backwards, shifting more weight on the rear wheel, reducing the “fishtailing” effect at the rear wheel (caused by the rear trying to overtake the front).
Weight on Handlebars
The suspension of the bike was designed to absorb bumps, isolating them from the frame as far as possible whilst providing feedback to the rider on what the front wheel is doing grip-wise. The front wheel will move around, both up and down and turn left to right in response to the road. This, contrary to what first instincts tell you is actually totally normal.
The handle bars are to steer the bike, NOT TO HOLD ON TO. When a rider holds on tightly to the bars, he restricts the ability of the suspension to react in the way it was designed to. Many modern sportsbikes are set up to steer quickly, having steep angles of rake (the angle of the front forks relative to the vertical). The trade-off for quick steering is that the bike can feel a little nervous when charging hard out of a corner and with may even give a little “head shake”. Within limits, this is fine and the reason why steering dampers are commonly fitted. It is important to allow the bike to do this- fighting it by holding on tightly will only worsen the situation.
In addition, holding the handlebars/clip-ons tightly will reduce the amount of feedback you get through them. This feedback is critical to knowing how the front end is doing. Holding on tightly will delay getting this feedback giving less time and margin to adjust accordingly.
Holding on tight to the handlebars will ruin a bike suspensions ability to correct itself, so don’t– hold the handlebars/clip-ons only tight enough to operate the throttle. Doing so means placing more weight on the footpegs and gripping the tank with your knees.
Preparing for the Corner
Getting the right corner entry speed is critical to negotiating a corner well. Enter too fast and you will either have to bank the bike over further than you are comfortable with or back off the throttle and risk going off the tarmac by transferring too much weight forward and experiencing a “low side”
Go in too slow and you will not be able to use the full extent of track available and lean angle. Because of this, better too slow than too fast because you can accelerate whilst banked over.
To prepare for a corner, pick your corner entry point- a fixed point on the road or track where you will commit to the corner, brake and downchange the gears to set the correct engine speed and bike speed, hang off if necessary and use the throttle to fine-tune the speed of the bike. ONLY ONCE THESE ARE SET SHOULD YOU ENTER THE CORNER. Give yourself time to do this– if in doubt, do it sooner.
Lower gearing ratio
When the bike is banked, the contact of the tire with the tarmac is on the side of the tire reducing the effective diameter of the tire. This causes the rear tire to turn slightly faster relative to the engine which is the same as dropping down a gear.
Because of this do not enter the corner with the engine speed too close to the rev limit or the engine speed may bounce off the rev counter mid turn destabilizing the bike. This also causes the speedometer to over-read in a corner. If used well, this effect can be utilized advantageously by keeping the engine on the boil even though speed is dropping as the bike enters the apex. It is also because of this that throttle should be applied early in the corner to keep weight bias rearwards. Conversely, when exiting the corners, it gives a similar effect to changing up when going from full lean to upright, meaning you can delay gearchanges until you are upright.
SUMMARY
Before the Corner:
Scrub off Excess Speed and Set up for corner by
• Apply Brake if required
• Set gears to give correct engine speed for corner
• Hang off if required
• Use Throttle to fine-tune corner entry speed
To Enter the Corner:
• Look for the apex as aim point
• Push handle bar and opposite footrest to bank bike over whilst setting body for lean angle required
In the Corner
Do not constantly adjust the steering angle
Apply throttle to shift weight rearwards
Look for exit aim point
Increase throttle as radius of corner increases
Exiting the Corner
• Bring bike to upright by pushing opposite handlebar and footpeg to corner entry
• Climb back to upright position
• Apply as much throttle as possible
• Aim for next corner entry point
Human instinct is not designed for motorcycles and needs to be reprogrammed to be useful.
Last Word:
All of the above is a lot to remember for a single corner. Successfully doing all of this for a corner is probably the most rewarding aspect of biking. Doing two corners in a row successfully is much more difficult. This is why sportbikers will happily go round and round a 15 corner circuit like Sepang in search of that elusive “perfect lap” without getting bored. Do it right and you will find that someone else can still do it faster than you. “How is that possible? Maybe I’m exiting this corner too slowly”. Changing this will upset the whole rhythm of your laps requiring you to change the way you ride the circuit and relearn it all over again. Changing how you take one corner affects how you take the next and so on. It is this which it makes so challenging, interesting and rewarding. It is also this which will improve your riding skills in ways you never thought possible.
This document is only intended as a pointer of where to look to improve you riding skills. It is not a substitution for proper coaching by trained instructors who can observe your riding style and give feedback more appropriate to the particular hurdles that may be blocking the way to improving your riding.
Tunku Johan Mansur
9th March 2003
19th May2004 (second rewrite)
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