Steering a motorcycle is a very interesting topic, it has caused heated arguments in pubs, I know of people who actually ride motorcycles who point blank refuse to believe how it really works and very strangely it has never been part of the Compulsory Basic Training syllabus. ( my instructors teach it anyway ).
Steering is some thing that most riders do without thinking about it especially if they have ever ridden a push bike at some time and because riders are steering instinctively they never learn how to exploit just how agile motorcycle are. Remember the best way to avoid an accident is to be somewhere else.
What really confuses the issue is that how you steer changes with the speed of the bike, I will explain that below.
It is a subject than can get very technical and or mathematical as a quick Google search will show.
I am going to ignore all of the theoretical stuff and just explain what works, and what doesn’t. If you want to explore the theory behind steering motorcycles then go ahead but this is not the place for it.
The speed bands below are typical for bikes/scooters but will vary depending on how your bike is designed etc.
Slow speed ( typically 0-15 mph )
Below about 15mph the dynamic forces affecting steering are very low and are very easily over ridden by the rider shifting weight and/or turning the handle bars. If you want to turn left then lean a little left and steer a little left and you will go left. You will need to balance the bike at the same time by putting in a little speed, and you could easily be using some slow speed control depending on the bike you are on. To bring the bike back upright to stop turning is usually a combination of the rider shifting weight, straightening the handle bars and or speeding up a little.
All of this generally comes naturally as the bike is reacting in a way you would expect.
Any problems with steering at slow speeds are almost always problems with slow speed control or caused by the rider looking at the obstacle they are trying to avoid instead of looking where they are trying to go ( you will go where you look ).
Problems can some times arise because the rider has poor coordination/ low confidence/ or is feeling stressed in a training or test situation.
Intermediate speeds ( typically 15 - 25 mph )
If you are “ tuned “ into your bike you will feel it go through this stage if you are picking up speed slowly. The steering might feel a bit mushy and the bike does not feel all that stable. Interestingly a lot of new riders on a CBT end up riding at this speed, they know/want to go faster but the mushy feel of the bike at this point stops them going any quicker.
Higher speeds ( 25 - 70 )
As the speed picks up the dynamic forces on the bike start to work properly, the wheels are spinning fast enough for the gyroscopic effects to be felt and the castor action of the steering geometry will also keep the bike stable and wanting to go in a straight line.
When you are travelling at these speeds to change direction you need to COUNTER steer.
If you want to lean left/turn left you need to push the left hand handle bar away from you.
If you want to lean right/turn right you need to push the right hand handle bar away from you.
I have chosen those words carefully !
Some riders when they hear this think I mean push the handlebars down, this isn’t what I mean and any way the handle bars don’t move down!
If you are not sure about this sit down, hold out you hands and imagine holding a set of handle bars, or use a broom handle. To lean/turn left you steer out of the turn by pushing away with your left hand.
OK what is going on here ? There are two things happening, fortunately they reinforce each other.
Firstly now you have some speed on the bike the front wheel is spinning fast enough for it to become a gyroscope, when you push the left hand side of the wheel spindle away from you the gyroscopic forces make the wheel lean left. As the wheel is fixed to the rest of the bike the bike will lean as well. Push right and you will lean right. If you can get hold of the wheel from a push bike try it with and without the wheel spinning and you will see what I mean.
The other factor here is steering the front wheel away from underneath the bike making it fall into the corner. When you push the left hand handle bar away from you the front wheel moves on the road surface to the right, making the bike lean left.
Do not wait until you get to a corner to try this, find a quite wide road preferably with little if any cross-fall/camber. Ride in the middle of your lane, your speed should be 30mph or a little more. Gently push the left hand bar away, feel how the bike responds, if nothing seemed to happen then push a little harder, don’t shove ! Gently push the right hand bar, play with it and get a feel for how the bike changes direction.
Next learn to lean with the bike as you push on the bars. The harder you push the quicker the bike will lean and change direction. If you are leaning left and need to lean farther left to tighten the turn push a little harder on the left hand bar and you will lean farther left.
Most bikes will need some force on the handle bars to change direction, but once they have leant into the turn they will need less pressure on the handle bar to hold the line. If you are completely neutral about the force you are putting on the handle bars then most bikes will gently straighten up.
Once you get the hang of counter steering it becomes very easy to position the bike exactly where you want to be, change direction when and by how much you need, and change the line in a corner if the corner tightens up/straightens out.
You can use counter steering to lift the bike back up out of a corner, but it is wiser and generally more stable to use the throttle to increase the speed.
What can go wrong ? Actually very little if you are smooth and progressive, but it is very important you know and understand what the bike will do when you put pressure into the handle bars so make a point of practicing counter steering until you are confident with it.