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      04-19-2007, 10:37 PM   #23
GregL
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Quote:
Originally Posted by Raider View Post
not true, it's very hard to lose control of a bike if ur going straight...


gyroscope effect...even if you hit huge bump, become airborned, chances are you're gonna land and keep going...
Is that so, I guess it makes sense when I think about it, I'm glad I learned something today
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      04-19-2007, 10:38 PM   #24
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do you know what the gyroscopic effect is lol...because thats not it...that refers to if the axis is tilted the resulting force will be applied 90* ahead in the direction of rotation and in the same direction of the applied force. which means if you hit a big enough bump your either going side ways or straight foward at 240mph depending on how you hit it.
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      04-19-2007, 10:40 PM   #25
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Quote:
Originally Posted by GregL View Post
Is that so, I guess it makes sense when I think about it, I'm glad I learned something today

Yep, i been riding bikes for many years...if you ask any bikers, once you're on a straight and you're going fast...it's very stable, and very hard to lose control...you can jump off the bike and it'll keep going and going till the tires stop spinning, or it hits something....
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      04-19-2007, 10:41 PM   #26
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Originally Posted by chade7320 View Post
do you know what the gyroscopic effect is lol...because thats not it...that refers to if the axis is tilted the resulting force will be applied 90* ahead in the direction of rotation and in the same direction of the applied force. which means if you hit a big enough bump your either going side ways or straight foward at 240mph depending on how you hit it.


did you wikipedia this just now?
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      04-19-2007, 10:44 PM   #27
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Quote:
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Yep, i been riding bikes for many years...if you ask any bikers, once you're on a straight and you're going fast...it's very stable, and very hard to lose control...you can jump off the bike and it'll keep going and going till the tires stop spinning, or it hits something....
So is this why you see those guys on tv standing on the seat when going at speed, or when people fall off during a speedrun and the bike just keeps going and going?

I have a friend who used to be a huge motorcycle fan, until one day he couldn't stop on a slick road, smacked into the front fender of a Volvo that ran a stop sign and flew over the hood... yeah... he still hasn't gotten back on one yet.
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      04-19-2007, 10:46 PM   #28
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Quote:
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did you wikipedia this just now?
No im actually a pilot, and when i was flying prop planes thats one of the things you study, the propeller spinning creates the gyroscopic effect which is of the left turning tendency's of a prop plane. On the ground and during climb out.
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      04-19-2007, 10:47 PM   #29
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Im not saying what you are saying is wrong, thats just not the name of it because that contradicts what your saying will happen.
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      04-19-2007, 10:53 PM   #30
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Quote:
Originally Posted by chade7320 View Post
Im not saying what you are saying is wrong, thats just not the name of it because that contradicts what your saying will happen.

i have no clue on what you're referring to with the plane....we're talking about 2 wheel vehicles here...


Gyroscope effect, atleast when speaking of bikes, mean that once it starts spinning and going, it creates more force, and in turn, resists falling over...

same thing on a bicycle, when you pedal real fast then let go, the bike become stable and keeps going straight, now do that at low speed and it'll fall over, or it's harder to keep upright as you have to use ur balance, gyroscope effect takes care of that by distributing the force of the spinning wheels and keeping you upright....
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      04-19-2007, 11:01 PM   #31
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Quote:
Originally Posted by GregL View Post
So is this why you see those guys on tv standing on the seat when going at speed, or when people fall off during a speedrun and the bike just keeps going and going?

I have a friend who used to be a huge motorcycle fan, until one day he couldn't stop on a slick road, smacked into the front fender of a Volvo that ran a stop sign and flew over the hood... yeah... he still hasn't gotten back on one yet.


I can ride a motorcycle upright at 100mph and you can throw a 30 lb medicine ball at the side of me, and i wont' fall over...it'll just ricochet off me, veer me off course, might wobble a bit, and then continue to stay upright...


you can lose control of bike when ur going straight is if u hit something head on, or if you upset the bike's telemetry dramatically, like grab the handlebars and turn it....funny thing is, if you're turning the handlebar to the left, the bike is gonna lean right....
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      04-20-2007, 07:39 AM   #32
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If the bike is vertical and the wheels are spinning fast, any leaning motion left or right will be resisted and the bike will want to right itself to the vertical position. You can feel these forces if you take a bike wheel, and stand on a rotary platform. Get the wheel spinning really fast, and then after having it in the vertical position, try leaning it right or left.

These forces help bikes be incredibly stable and uprighting in a straightline..
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      04-20-2007, 07:48 AM   #33
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Chade what you are talking about with single prop airplanes is more Newton than gyroscopic. For every action, there is an equal and opposite reaction. Your engine is rotating the propeller. The opposite reaction is your plane wanting to twist opposite the rotation of the propeller. The fuller the throttle, the more you are going to feel this effect..

Where gyros do come into effect is your attitude indicator (artificial forizon) (before electronics) That is a gyroscope that gets spinning up fast in a fluid. When you change your angle of attack, the ball stays in the same relative position, so to you, in the gage, you see the horizon move relative to the gage, which is fixed. You are moving, and relative to the earth the gyros are staying stationary.. Enabling you to see your attitude relative to the horizon..
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      04-20-2007, 07:59 AM   #34
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Think about helicopters for an example. You have a huge single prop. The helicopter wants to twist hard opposite the rotor's rotation. To counterbalance this torque, you have a tail rotor, another rotating blade. Notars are a new form where they use high pressure air direction out of a nozzle to counteract the torque. One way or another you need to counteract this torque. If you watch early videos of helicopter development you could see a lot of them spin out because the torque wasn't counteracted correctly. It seemed it took them a lot of tries to figure this out right..

In planes it's the same thing, just now horizontal instead of vertical. But you have huge wings with lift pushing up from the bottom of them to counteract the force. You're still going to feel its effects, especially at full throttle. And it is also most likely is easier to bank one direction in a single prop plane than the other.
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      04-20-2007, 08:09 AM   #35
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Quote:
Originally Posted by Raider View Post
I can ride a motorcycle upright at 100mph and you can throw a 30 lb medicine ball at the side of me, and i wont' fall over...it'll just ricochet off me, veer me off course, might wobble a bit, and then continue to stay upright...
Depends who is throwing the medicine ball and how fast they can throw it..
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      04-20-2007, 08:51 AM   #36
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Quote:
Originally Posted by Josh49 View Post
Depends who is throwing the medicine ball and how fast they can throw it..

just giving an example, if it's was fired out of a cannon then of course i'd be knocked off.
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      04-20-2007, 09:08 AM   #37
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Quote:
Originally Posted by Raider View Post
just giving an example, if it's was fired out of a cannon then of course i'd be knocked off.


I know.. I'm just busting your chops.. Hence this little dude..
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      04-20-2007, 11:44 AM   #38
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Raider, Glad you chimed in...

Yeah, as a lifetime Motorcyclist (the 335i is my second car in a year after 12 years of NO car at all) What Raider is talking about is Correct.

A motorcycles wheels weigh anywhere from 20-50lbs. They create a serious amount of Gyroscopic effect that stabilizes a motorcycle at anything more than about 15MPH. At over 100 most street bikes become VERY Hard to turn, on Sport bikes at about 150 they become very hard to turn. This is why on racing bikes you'll see a lot of carbon fiber wheels and super lightweight magnesium wheels, allows for lighter steering and acceleration everywhere, though they sacrifice stability.

This effect is also why folks thinking that you steer a street bike by leaning your body one way or the other are fooling themselves. Keith Code has a bike set up just to show folks that "Body Steering" is ineffective in changing direction and that to change direction in a hurry on any bike, it's all about counter steering, whether you know you're doing it or not.

Believe it or not, steering a street bike is all about steering the OTHER direction.

If I want to turn left, I actually push forward on my left grip, actually trying to TURN the bars to the right. It's called counter steering and is how all street bikes turn. Some riders just don't know it yet. Push right to go right, push left to go left.

At high speeds up around 180-190 I would actually have to kind of lever myself from my left peg to my right bar if I wanted to effect a quick lane change. QUICK being a relative term. At those speeds (Clearwater-Tampa on the Gandy Bridge) a mile every 18seconds or so, it would take about 70 seconds to cover the length of the 3 mile bridge. Some folks a lot longer, some a good bit less. At these speeds the bikes are amazingly stable, and if you DO crash? If you are wearing your leathers and don't hit anything? Pretty good chance you'll walk or at least limp away. Modern gear is pretty damned good.

Anyway, modern sport bikes are amazingly SAFE machines. Incredible Brakes, Superb handling, and power to get out of ANY trouble almost. Problem is that too many kids and delusionals climb on em' without even the most basic of fundamentals like counter steering, Front brakes provide 90% of your stopping power, and throttle control.

It's a pisser because there are so many "squids" out there on sport bikes that you simply cannot be out riding one anymore without running into issues from police, misguided vigilantes, and folk that plain old hate motorcyclists...


Sorry there I go again with the caffeine.
Here ya Go... To put things into perspective. Sorta remind us all NOT to tangle with a sport bike... Accept maybe on a good twisty mountain road. Suzuki Hayabusa Performance Data. The Hayabusa was THE performance "Hyperbike" of the last 7-years. Open class, STREET Bike, no racing pretense.

Now last year or so Kawasaki produced the ZX14 designed to be faster and better than the Suzuki. So far, the public isn't buying it, they are still buying more Hayabusa's as it's become a bit of a cult bike and every knobber, wanna be, and NFL Shit head feels they need one. But regardless it's a great streetbike. Comfy, Stable, reliable. :rocks:

Anyway, oh and yeah I work for a large Multi-line Motorcycle dealership here in the Northwest. From Harleys-Truimph- Yamaha's and everything in between.

Sorry for the book....
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      04-20-2007, 04:26 PM   #39
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I'd rather have an MV Agusta. Such gorgeous bikes.
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