Limit cornering on bikes

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SectorOne
166
Joined: Sun May 26, 2013 8:51 am

Re: Limit cornering on bikes

Andres125sx wrote:
Tue Mar 03, 2020 8:16 pm
Also, but they´re different effects. You´re talking about steer stability, wich is different to lean/angle stability. Both are necessary for a bike to continue rolling even without a rider onboard. Without the lean/angle stability the bike would crash to any side even if the steer is straight due to the forks angle (advance? it´s the translation from spanish, but not sure if that´s correct in english). Actually in those crashes I was talking about, the bike is leaned when the rider crash, and the bike straight up itself. Obviously the steer has no impact here, a straight steer is necessary for that to happen, but not enough
No as soon as the rider lets go of the bike, the bike does it´s own steering because of the geometry of the front forks.
It even as you have already noted, manages to overcome whatever little gyroscopic forces there were and stand itself back up without rider input.

As i said, the bike wants to fall down, say to the left, front wheel will start to turn left which causes it to stand back up again (remember countersteering makes it turn, steering makes it stand up)

Andres125sx wrote:
Tue Mar 03, 2020 6:00 pm
Agree, same as a vertical wheel that is spinning will stay spinning vertically without any outside force acting on it, wich is exactly the case we´re talking about with a motorcycle staying vertical by itself and needed some extra force to lean it into a corner
But we see many many times when these types of crashes happen, the bike is leaned over at some point but then magically steers itself straight up.

Now we´ve already established that a spinning wheel without outside interaction can´t change it´s angle, it wants to spin in whatever direction it is spinning in.

So when the bike steers itself straight like we see on those shots what happens? The bike itself through the geometry steers itself which means unlike countersteering which makes a bike lean it will do the opposite and stop any leaning and stay straight.

Andres125sx wrote:
Tue Mar 03, 2020 6:00 pm
Not here, at least in 1997 wich is when I got my motorcycle driving license
So for 23 years of motorcycling only now do you discover that in order to turn a motorcycle you actually countersteer.
You are one lucky dude to be alive
You could have had a situation where you had to make a super fast direction change and all you would have done is try to shift weight rather then countersteer hard.

Andres125sx wrote:
Tue Mar 03, 2020 6:00 pm
and I´ve watched dozens of videos about riding techniques along the years...
And i wonder to myself what type of videos are these you are talking about?

Andres125sx wrote:
Tue Mar 03, 2020 6:00 pm
90 degrees is unreal. What about 40 degrees? Fair question, you´ve agreed tilting the bike will be more difficult due to the gyroscopic effect wich is obvious for anyone who has ever riden a bike. But you continue denying it will straight up itself. I have always assumed it will, but you´re managing to make me doubt, not seriously but it´s a start
90 degrees, 40 degrees, 34,45456 degrees it does not matter.
Forget about the motorycle, lets just use the experiment in the video you provided.
A simple wheel being spun really fast.

A wheel that is spinning will want to spin in whatever direction you put it.

This is why carbon wheels are so lauded, they make the bike easier in transitions from left to right.
Same with counter-rotating shaft, while yes it helps keep the front wheel down a little bit it also cancels some of the gyroscopic effects produced by the wheels. Again making the bike easier to flick from side to side.
"If the only thing keeping a person decent is the expectation of divine reward, then brother that person is a piece of sh*t"

Andres125sx
164
Joined: Tue Aug 13, 2013 9:15 am

Re: Limit cornering on bikes

SectorOne wrote:
Tue Mar 03, 2020 9:05 pm
Andres125sx wrote:
Tue Mar 03, 2020 8:16 pm
Also, but they´re different effects. You´re talking about steer stability, wich is different to lean/angle stability. Both are necessary for a bike to continue rolling even without a rider onboard. Without the lean/angle stability the bike would crash to any side even if the steer is straight due to the forks angle (advance? it´s the translation from spanish, but not sure if that´s correct in english). Actually in those crashes I was talking about, the bike is leaned when the rider crash, and the bike straight up itself. Obviously the steer has no impact here, a straight steer is necessary for that to happen, but not enough
No as soon as the rider lets go of the bike, the bike does it´s own steering because of the geometry of the front forks.
It even as you have already noted, manages to overcome whatever little gyroscopic forces there were and stand itself back up without rider input.
Little gyroscopic forces? What is your experience riding motorcycles SectorOne? Any?

SectorOne wrote:
Tue Mar 03, 2020 9:05 pm
Now we´ve already established that a spinning wheel without outside interaction can´t change it´s angle, it wants to spin in whatever direction it is spinning in.
That´s first law of Newton, not gyroscopic effect

SectorOne wrote:
Tue Mar 03, 2020 9:05 pm
So for 23 years of motorcycling only now do you discover that in order to turn a motorcycle you actually countersteer.
You are one lucky dude to be alive
At some point it would be great if you stop your unbereable arrogance mate

The funny part is you seem to enjoy little to zero experience in motorcycles, but even so you think you know better than anyone. Wow.

I´ll stop here, discussing with people this arrogant is pointless and can only harm the forum

Greg Locock
Greg Locock
225
Joined: Fri Jun 29, 2012 11:48 pm

Re: Limit cornering on bikes

As an aside someone built a bike with counterrotating flywheels on the wheels, to eliminate gyroscopic effects. The results blew a lot of armchair theories out of the water.
“A Bicycle Can Be Self-Stable Without Gyroscopic or Caster Effects.” J. D. G. Kooijman, J. P. Meijaard, Jim M. Papadopoulos, Andy Ruina, and A. L. Schwab. Science, April 15, 2011, Vol. 332, No. 6027, Pg. 339-342. DOI: 10.1126/science.1201959

SectorOne
166
Joined: Sun May 26, 2013 8:51 am

Re: Limit cornering on bikes

Andres125sx wrote:
Wed Mar 04, 2020 7:56 am
Little gyroscopic forces? What is your experience riding motorcycles SectorOne? Any?
Relatively speaking yes.
Several years. Actually going to the dealer tomorrow to check out my Panigale V2 i ordered.
Dying to hear the L-twin with the akrapovic slip-ons.

Andres125sx wrote:
Wed Mar 04, 2020 7:56 am
That´s first law of Newton, not gyroscopic effect
It makes no difference what it is.
Your understanding of a spinning wheel magically standing itself upright has no basis in reality.

Andres125sx wrote:
Wed Mar 04, 2020 7:56 am
At some point it would be great if you stop your unbereable arrogance mate
Im really trying but im talking to a guy who talks so much and so confidently about steering motorcycles when he does not even understand the most fundamental part of leaning a motorcycle.
"If the only thing keeping a person decent is the expectation of divine reward, then brother that person is a piece of sh*t"

Ringleheim
Ringleheim
9
Joined: Thu Feb 22, 2018 9:02 am

Re: Limit cornering on bikes

What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.

Andres125sx
164
Joined: Tue Aug 13, 2013 9:15 am

Re: Limit cornering on bikes

Ringleheim wrote:
Thu Mar 05, 2020 8:38 pm
What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.
According to some, Marquez is really lucky to be alive yet, as he probably don´t understand all the physics behind motorcycles

Andres125sx
164
Joined: Tue Aug 13, 2013 9:15 am

Re: Limit cornering on bikes

SectorOne wrote:
Thu Mar 05, 2020 8:21 pm
Andres125sx wrote:
Wed Mar 04, 2020 7:56 am
At some point it would be great if you stop your unbereable arrogance mate
Im really trying but im talking to a guy who talks so much and so confidently about steering motorcycles when he does not even understand the most fundamental part of leaning a motorcycle.
At least you recon your arrogance, even if using wrong assumptions to justify yourself...
Andres125sx wrote:
Fri Feb 28, 2020 7:58 am
Or that´s what I guess, I´ve never studied the effect

mertol
7
Joined: Tue Mar 19, 2013 9:02 am

Re: Limit cornering on bikes

You are thinking the limit is an infinitely thin line. But irl there are no perfect conditions. The track always has small bumps and what not so the limit is fuzzy. If you are on the exact limit on this bump you might be over the limit on the next one a fraction of a second later. Since you can't change the stance of the bike hundreds of times per second you tend to ride on the safer side of the fuzzy limit and be on the limit during *some* of the bumps which repeated several times per second can feel you are on the limit the whole time.

bdr529
59
Joined: Fri Apr 08, 2011 6:49 pm

Re: Limit cornering on bikes

johnny comelately wrote:
Sat Feb 22, 2020 1:10 pm
The normal state of a motorbike is on its side
I'm guessing you've seen me race

Jolle
Jolle
132
Joined: Wed Jan 29, 2014 9:58 pm
Location: Dordrecht

Re: Limit cornering on bikes

Ringleheim wrote:
Thu Mar 05, 2020 8:38 pm
What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.
Believe me, certainly at speed... you feel all those forces very well not so much a dance as a rodeo Even the amount of RPM's while turning you feel, it makes a difference if you do 180 in third or fourth.

bdr529
59
Joined: Fri Apr 08, 2011 6:49 pm

Re: Limit cornering on bikes

these might help clear up some things about this topic

Keith Code was the go to guy back when I raced (80's) it was just a book then

And a few from the California Superbike school, 7 part series
these would be helpful for anyone that rides, race track or street

J.A.W.
J.A.W.
109
Joined: Mon Sep 01, 2014 4:10 am
Location: Altair IV.

Re: Limit cornering on bikes

Ringleheim wrote:
Thu Mar 05, 2020 8:38 pm
What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.
There's a bit more to it than that..

M.M. aint some circus-performing ape that arrives in a Honda box, & is put on a bike!

He's a thorough professional who has dedicated his life to mastering this sport, & yeah ok,
his 'cat-quick' reflexive reaction times are remarkable, (& he is for sure, a 'real cool cat')
but of course he'd have a thorough engineering understanding of the Honda's relevant systems,
& thus is able to provide an rider's operational commentary to match the telemetry readings...
"Well, we knocked the bastard off!"

Ed Hilary on being 1st to top Mt Everest,
(& 1st to do a surface traverse across Antarctica,
in good Kiwi style - riding a Massey Ferguson farm
tractor - with a few extemporised mod's to hack the task).

Andres125sx
164
Joined: Tue Aug 13, 2013 9:15 am

Re: Limit cornering on bikes

J.A.W. wrote:
Sat Mar 07, 2020 4:25 am
Ringleheim wrote:
Thu Mar 05, 2020 8:38 pm
What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.
There's a bit more to it than that..

M.M. aint some circus-performing ape that arrives in a Honda box, & is put on a bike!

He's a thorough professional who has dedicated his life to mastering this sport, & yeah ok,
his 'cat-quick' reflexive reaction times are remarkable, (& he is for sure, a 'real cool cat')
but of course he'd have a thorough engineering understanding of the Honda's relevant systems,
& thus is able to provide an rider's operational commentary to match the telemetry readings...
If you want to simplify things to absurd as you usually do, including this message, yes, MM as any other top rider, actually is a circus-performing ape that arrives to the box and is put on a bike. To put things on perspective, ignore Marquez and think on those Moto3 riders who are 15 years old but master their bikes to a point anyone from this forum should be jelous. Do you think those teenagers know something about engineering? Or maybe you think like SectorOne that they, like any rider who does not master the engineering part, are lucky to be alive?

Mastering a bike is completely different to understanding the physics behind, and usually none master both. Assuming top riders who usually stopped their studies well before 18 understand everything from motorcycling engineering is simply laugable

J.A.W.
J.A.W.
109
Joined: Mon Sep 01, 2014 4:10 am
Location: Altair IV.

Re: Limit cornering on bikes

Andres125sx wrote:
Sun Mar 08, 2020 10:10 am
J.A.W. wrote:
Sat Mar 07, 2020 4:25 am
Ringleheim wrote:
Thu Mar 05, 2020 8:38 pm
What is cool about this entire conversation is that we can all agree there are some complicated physics going on in top level motorcycle racing! It's all quite interesting, and not easy to understand or define.

And yet a kid like Marc Marquez can hop on one of these MOTO GP bikes and make it sing and dance, while having (for the most part) no understanding whatsoever what he is doing, or how it all works.

He just knows how to make the thing fly on a race track.

It's really quite incredible.
There's a bit more to it than that..

M.M. aint some circus-performing ape that arrives in a Honda box, & is put on a bike!

He's a thorough professional who has dedicated his life to mastering this sport, & yeah ok,
his 'cat-quick' reflexive reaction times are remarkable, (& he is for sure, a 'real cool cat')
but of course he'd have a thorough engineering understanding of the Honda's relevant systems,
& thus is able to provide an rider's operational commentary to match the telemetry readings...
If you want to simplify things to absurd as you usually do, including this message, yes, MM as any other top rider, actually is a circus-performing ape that arrives to the box and is put on a bike. To put things on perspective, ignore Marquez and think on those Moto3 riders who are 15 years old but master their bikes to a point anyone from this forum should be jelous. Do you think those teenagers know something about engineering? Or maybe you think like SectorOne that they, like any rider who does not master the engineering part, are lucky to be alive?

Mastering a bike is completely different to understanding the physics behind, and usually none master both. Assuming top riders who usually stopped their studies well before 18 understand everything from motorcycling engineering is simply laugable

No Andres, you surely cannot be serious...

What is "laughable", is that you can possibly imagine that professional experts in their field,
do not/are not fully capable of, (even when expected to) - providing expert feedback on the
basis of a very real, & thorough, understanding of the needful rider-feedback systems of the
super-high performance machine - they must master to enable the very best likehood of a title-win.

(Ask yourself why ex-champions, yet still fairly recent, & fit/active, such as Stoner & Lorenzo
are so sought after by teams to provide even more expert test-rider feedback...)
"Well, we knocked the bastard off!"

Ed Hilary on being 1st to top Mt Everest,
(& 1st to do a surface traverse across Antarctica,
in good Kiwi style - riding a Massey Ferguson farm
tractor - with a few extemporised mod's to hack the task).

Airshifter
10
Joined: Sat Feb 01, 2020 2:20 pm

Re: Limit cornering on bikes

Jolle wrote:
Tue Mar 03, 2020 8:47 pm

Basically, you turn the wrong way for a moment to lean the bike over. This is the best and only way to take a corner for us mortals on a street bike. Good chance you're doing this automatically without realizing.

I would almost guarantee that when a person first rides a bicycle or motorcycle, they have no idea they are countersteeting.... ever! I know I certainly didn't, and went from being a terror on a bicycle, to dirt bikes, to street bikes before I really understood how I was steering.