Wheelie

[garb55]

Back in 2008 I tried doing a wheelie with my GS Sm5
I sat on the back seat to get traction and counter the front end weight
I only was able to get the front wheels 2 inches off the ground before the nanny shut me down
I will tell you when you see that 5 ft. wide front end begin to come up it is a little [no A Lot ]scary

 

[jtpollock]

Well, after a week of practice I've finally managed to get a good wheelie out of the F3.

I can get the front wheels about 2 feet off the floor and hold it there for around 100 yards, the hard part is stopping the bike from lurching either left or right.

Any one else tried this?

Ant

just for fun Angular momentum and torque

See also: Torque § Definition and relation to angular momentum
Newton's Second Law of Motion can be expressed mathematically,

or Force = mass × acceleration. The rotational equivalent is

or torque = moment of inertia × angular acceleration. Because angular acceleration is the time derivative of angular velocity, this is equivalent to

Rearranging into a form suitable for integration,

and

and integrating with respect to time,

Therefore, a torque acting over time is equivalent to a change in angular momentum. The constant can be interpreted as the initial angular momentum of the body, before the torque began to act. In particular, if torque

then angular momentum

[SUP][15][/SUP] That is, if no torque acts upon a body, then its angular momentum remains constant. Conversely,

or Angular momentum = moment of inertia × angular velocity, and its time derivative is

Because moment of inertia is constant,

is zero, and

which, as above, reduces to

what do you think... jtpollock

Oh ya I also forgot about the center of mass.

 

[Bob Denman]

Maxed out my BS O'meter...

:shocked: Yours too??

 

[beadaholic]

haha yeah yeah yeah, don't believe until I see the video and even then it might be faked, remember the paramagnetic paint videos? The car changes colors and people freak out and jump back, well that is a fake, anything can be fake....

 

[TommyBwell]

just for fun Angular momentum and torque

See also: Torque § Definition and relation to angular momentum
Newton's Second Law of Motion can be expressed mathematically,

or Force = mass × acceleration. The rotational equivalent is

or torque = moment of inertia × angular acceleration. Because angular acceleration is the time derivative of angular velocity, this is equivalent to

Rearranging into a form suitable for integration,

and

and integrating with respect to time,

Therefore, a torque acting over time is equivalent to a change in angular momentum. The constant can be interpreted as the initial angular momentum of the body, before the torque began to act. In particular, if torque

then angular momentum

[SUP][15][/SUP] That is, if no torque acts upon a body, then its angular momentum remains constant. Conversely,

or Angular momentum = moment of inertia × angular velocity, and its time derivative is

Because moment of inertia is constant,

is zero, and

which, as above, reduces to

what do you think... jtpollock

Oh ya I also forgot about the center of mass.

Thats what I meant to say

 

[TommyBwell]

The rear wheel loading is so low that traction is the issue. Even on the tackiest surface the rear tire spins. (I haven't tried a drag strip, yet.)

You see fat tires on F1 cars but they have thousands of pounds of downforce from the bodywork. Without the downforce they'd blow the tires.

We have a fat tire but no downforce. Simple physics, right?

I could wheelie my Grom. That is a 9 HP economy bike. It was just a matter of shifting my weight. (My ZX-14R wheelied, too! Come to think of it, every motorcycle i ever had did wheelies! But in a lot of cases a lot of "body-english" was needed.)

I think that people who think they are doing wheelies are really misinterpreting the chassis rocking back on the (undersprung) rear suspension.

I'd love to be proven wrong, though!

i agree with what you are saying but F1 cars get off the line with minimal wheel spin (due to electronic wizardry) but the downforce does not come into play until they start carrying some speed. As soon as JT does the math I'll show you the physics of it.

 

[Orange Spyder Man]

Video / or it didn't happen

yeah.... and cows fly.... :roflblack: I guess next some dreamer will tell us he did a reverse wheelie ... :sour:

osm

 

[Pampurrs]

 

[Bob Denman]

:agree:

 

[ARtraveler]

Thats what I meant to say

All good stuff. I have a problem with the derivative of angular velocity part of the equation though. :roflblack::roflblack:

When I was out riding yesterday, I came up with a reply of Crikee, Cribby (I think that is a bit British/Welsh--but hopefully not offensive in any way).

 

[cribby]

HEE HEE

But I got a bit of a post going though didn't i?

My apologies but I just couldn't resist it!

 

[DrewNJ]

Sent from my SCH-I545 using Tapatalk

 

[Bob Denman]

But I got a bit of a post going though didn't i?

My apologies but I just couodn't resist it!

All is forgiven...
But do you have ANY idea how much damage you would do to the front end of the bike, if you dropped it back down hard from a two-foot Wheelie?? :shocked:

:roflblack:

 

[PrairieSpyder]

Well, after a week of practice I've finally managed to get a good wheelie out of the F3.

I can get the front wheels about 2 feet off the floor and hold it there for around 100 yards, the hard part is stopping the bike from lurching either left or right.

Any one else tried this?

Ant

I'll venture to say that no one else has done that.

I'd also want to see the video.

 

[jtpollock]

i agree with what you are saying but F1 cars get off the line with minimal wheel spin (due to electronic wizardry) but the downforce does not come into play until they start carrying some speed. As soon as JT does the math I'll show you the physics of it.

Thanks buy that math is over my head I do have a CAD drawing that I was trying to figure it out.

The pivot point is around 7.5" off the ground the wheel base is 67.3" long with a rider around 200 Lb.'s and the dry weight of the F3 being 850 Lb.'s you have 96 ft. Lb.'s of torque @5000 rpm.

I was hopping that someone out there had more math skills just to figure out the science :yikes: .

I thought BOB would have the answer? just having fun :yes::yes::yes: jtpollock

 

[Bob Denman]

Who was it, that pulled our legs with his "Dream Ride" on a new RT a couple of years ago?
Was it Winger? :dontknow:

 

[Pirate looks at --]

Come on!

Now if you had said you did that wheelie in reverse we would have believed you!:roflblack::roflblack::roflblack:

 

[Gumbeau]

Right

Now if you had said you did that wheelie in reverse we would have believed you!:roflblack::roflblack::roflblack:

Whatever you're smoking, share it

 

[TommyBwell]

Of course I'm the stupid new guy who bit. I was thinking you sit lower and further back if you popped the clutch you could get it up. You see guys doing wheelies on some crazy stuff. When I saw there was not a single video on YouTube I knew I had been bamboozled.

 

[Pirate looks at --]

Shhhh

Of course I'm the stupid new guy who bit. I was thinking you sit lower and further back if you popped the clutch you could get it up. You see guys doing wheelies on some crazy stuff. When I saw there was not a single video on YouTube I knew I had been bamboozled.

Try it in reverse!