Counter steering at speed >100k's

[Motu]

at < ~20km/h steering takes is done 'normally'

at > ~20km/h countersteering is used

so,so,so,so what happens at the point in the middle use neither? (it's disturbing me...)

I've heard that on LSR bikes the steering dynamics change throughout the speed range,maybe it's cyclic,a waveform.If speed was unlimited how many times would it happen?

[Bonez]

This countersteering thing is something I understand but am reluctant to try at speed, ( for me this equals over 60km) mainly cos I am scared of getting it wrong and losing control. I know this is ridiculous but I am still too chicken to do a rapid swerve around an object on the road, Pete has it down to a fine art and thinks it's cool. The same goes for getting the knee down a bit, on a tight corner, I think it's kinda tragic looking on a cruiser, but who knows one day I might have to try it in order to get around the bend, the scary thing is just how much lean can you have before losing it?, you really can't tell until you do can off can you?

After a while countersteering does become natural. trust me. As for knee downs-never had to do it to get around a corner yet.

[Quasievil]

I find dropping the insdie shoulder (shoulder on the inside of the corner)

helps push the bar for increased turning angle especially if I need to tighten up on a corner

[Wonko]

I've heard that on LSR bikes the steering dynamics change throughout the speed range,maybe it's cyclic,a waveform.If speed was unlimited how many times would it happen?

I would have thought that the physic's of counter steering would work at any speed, it's just that the effect of gravity would make the bike fall over before you noticed any real change in direction

[Jamezo]

I would have thought that the physic's of counter steering would work at any speed, it's just that the effect of gravity would make the bike fall over before you noticed any real change in direction

not necessarily; as I can discern, the ability of the bike to be turned by the countersteering force grows proportionally (possibly exponentially? I know the force experienced at the circumference of the wheel will be raised exponentially, but does this necessarily translate to the gyroscopic 'intertia'?) to the speed of rotation of the front wheel.

the question is, how does the ability of the bike to be turned by steering into the corners, change with the velocity of the bike itself? I guess we have to build a bike with wheels of minimal mass, to negate the gyroscopic force, and see how it's cornering behaviour changes with speed. that is if it will stay upright! I think a good compromise would be to have only the front wheel 'massless', and have the back wheel normal or maybe heavier to keep the bike upright.

sounds like a good physics thesis!

[WINJA]

A good rider will get to know his/her motorcycle's capabilities, this most definately includes how far over it is able to lean in a corner. There are several ways of obtaining this knowledge, for instance you can lean the bike over while it is stationary (with the help of another person) and see how far it will lean before any parts touch the ground! One day you may need to lean your bike far into a corner for emergency's sake and if you don't know the bikes limits you will probably bin it.

In saying all of that, if you ride like an absolute granny and freak out when the bike leans over & brake heavily on every corner you approach - forget about it! Leaning the bike over is supposed to be the fun part.

MAXIMUM LEAN ANGLE CAN REDUCE WITH SPEED AS SUSPENSION COMPRESSES

[WINJA]

not necessarily; as I can discern, the ability of the bike to be turned by the countersteering force grows proportionally (possibly exponentially? I know the force experienced at the circumference of the wheel will be raised exponentially, but does this necessarily translate to the gyroscopic 'intertia'?) to the speed of rotation of the front wheel.

the question is, how does the ability of the bike to be turned by steering into the corners, change with the velocity of the bike itself? I guess we have to build a bike with wheels of minimal mass, to negate the gyroscopic force, and see how it's cornering behaviour changes with speed. that is if it will stay upright! I think a good compromise would be to have only the front wheel 'massless', and have the back wheel normal or maybe heavier to keep the bike upright.

sounds like a good physics thesis!

A BIG PART OF CORNERING BEHAVIOUR IS DOWN TO CRANK WEIGHT. HAVE YOU EVER RIDDEN A GSXR600 AND GSXR1000 BACK TO BACK ON THE SAME ROAD. IF YOU HAVE A STANDARD 120 UP FRONT AND A 180 ON BOTH BIKES REARS RUN THE SAME GEOMETRY AND THE 600 TURNS FASTER ESPCIALLY ON THE 2ND AND 3RD CONSECUTIVE CORNER. THE BIKES DIFFERENCE IN WET WEIGHT IS MINIMAL

[Jantar]

not necessarily; as I can discern, the ability of the bike to be turned by the countersteering force grows proportionally (possibly exponentially? I know the force experienced at the circumference of the wheel will be raised exponentially, but does this necessarily translate to the gyroscopic 'intertia'?) to the speed of rotation of the front wheel.

the question is, how does the ability of the bike to be turned by steering into the corners, change with the velocity of the bike itself? I guess we have to build a bike with wheels of minimal mass, to negate the gyroscopic force, and see how it's cornering behaviour changes with speed. that is if it will stay upright! I think a good compromise would be to have only the front wheel 'massless', and have the back wheel normal or maybe heavier to keep the bike upright.

sounds like a good physics thesis!

The gyroscopic force, and hence the force required at the handlebars increases with the square of the rotational velocity.

Here's a simple experiment you can do at home that will answer most of the questions raised here:

Hang a single loop of string from the roof of your shed or garage.
Take a pushbike wheel and let one end of the axle hang in the loop of string while you support the other end of the axle so that the wheel is vertical as if on a bike.
With your free hand start the wheel spinning quite fast.
Let the wheel go so that it is now supported only by the string on one end of the axle.
The wheel will remain vertical as it spins.
The center of gravity (weight) of the wheel is offset from the point of suspension, trying to pull the unsupported end of the axle down. This is the same as you trying to counter steer.
The wheel instead of tipping down on that side will turn such that the direction of turn is 90 degrees lagging the force of gravity.
The turning effect will appear to increase as the wheel slows down, until eventually the force of gravity will overcome the gyroscopic force.

Counter steering is exactly the same, with the small exception that in trying to turn the wheel we actually cause the wheel to lean. It will not turn, but it can only lean by causing the whole bike to lean over with it. At higher speeds the amount of force required to cause the bike to lean doesn't change, but the handlebars will feel more rigid. That's because due to gyroscopic force they ARE more rigid. It is force applied in a turning diection, not any actual turning of the bars, that is multiplied into a change in angle of lean.

[notme]

Hey if you want nice sweeping and empty roads to practice all this theoretical physics on - or just to go for a ride, come out to Botany Downs area, heaps of back roads out this way! There are unfinished subdivisions that are totally car free on the weekends and open back roads that are nicely sealed and not full of potholes!

I'm always up for a ride on the weekends or a clear evening so PM/email me if you're keen!

[Jamezo]

The gyroscopic force, and hence the force required at the handlebars increases with the square of the rotational velocity.

Here's a simple experiment you can do at home that will answer most of the questions raised here:

Hang a single loop of string from the roof of your shed or garage.
Take a pushbike wheel and let one end of the axle hang in the loop of string while you support the other end of the axle so that the wheel is vertical as if on a bike.
With your free hand start the wheel spinning quite fast.
Let the wheel go so that it is now supported only by the string on one end of the axle.
The wheel will remain vertical as it spins.
The center of gravity (weight) of the wheel is offset from the point of suspension, trying to pull the unsupported end of the axle down. This is the same as you trying to counter steer.
The wheel instead of tipping down on that side will turn such that the direction of turn is 90 degrees lagging the force of gravity.
The turning effect will appear to increase as the wheel slows down, until eventually the force of gravity will overcome the gyroscopic force.

Counter steering is exactly the same, with the small exception that in trying to turn the wheel we actually cause the wheel to lean. It will not turn, but it can only lean by causing the whole bike to lean over with it. At higher speeds the amount of force required to cause the bike to lean doesn't change, but the handlebars will feel more rigid. That's because due to gyroscopic force they ARE more rigid. It is force applied in a turning diection, not any actual turning of the bars, that is multiplied into a change in angle of lean.

eg-zacktly!

teh smartness.

[inlinefour]

There is this thing I am trying to understand. Was at BRONZ's riding course a week ago and they taught us counter steering, all very well doing it at 60k's on the runway. But I was trying to pratice it when there no cars around on Sunday night, and I was trying to push the handle bars @ 100ks but they were solid as.

Now, am I doing something wrong? Or am I not pushing hard enought? Or is it just my bike?

cause I am scared of pushing too hard and going over. :spudwhat:

Either you will be knocked off or come off from going too fast. Personally I'd rather it was the latter as the only painfull accident involved an arse in a cage

[fritter]

Plus the VTR's bars are alot wider than more sportier bikes so i'd imgaine you'd need to put a bit more effort in, correct me id i'm wrong.

It's less effort to push on wider bars, not more. The sportier bikes tip easier coz they have sharper steering angles and stuff like that...

If you concentrate on pushing the bar with your elbows lower it makes a difference - so that you are pushing the bar forward rather than down.