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06-19-2013, 09:01 AM   #706
Dirty in all

Joined: Apr 2012
Location: Connecticut
Oddometer: 152
Quote:
 Originally Posted by Rucksta There are ways other than / in addition to handlebar input to balance gravity including but not limited body positioning, throttle opening and arc of turn. Stand beside your bike, left hand on the left grip, right hand on the grab rail and move the bike forward while maintaining full left lock. No homework or questions to answer just make your own obsevations. I'm not a big fan of Tony Foale's explainations. Link is to the a diagram only just in case you've never seen the experiment. http://www.tonyfoale.com/Articles/Balance/Img00003.gif Many staunch countersteering sceptics who have held the wheel have an epiphany. Sometimes you can actually see the penny dropping by the expression on their faces. Thing is if you spin the wheel really slowly the forces just are not present. And so the argument goes round and round - just like the bicycle wheel. The faster you spin it the stronger it gets. To me those who insist countersteering is the only way to turn a motorcyle are missing out on as much as those who instist countersteering is a myth. Maybe my question belongs in a different thread away from the zealots and sceptics.
I actually have no questions on the subject. I've been on a motorcycle since I was 3 and I'm now 43. You only said exactly what I said but in a long drawn out explanation. Now you want to throw in the rest of it. I'm talking about STEERING, thought I read that somewhere in the thread title.

06-19-2013, 09:38 AM   #707
Boon Booni
Red Clay Halo

Joined: Aug 2003
Location: Richmond, Va
Oddometer: 12,137
Quote:
 Originally Posted by Rucksta . http://www.tonyfoale.com/Articles/Balance/Img00003.gif Many staunch countersteering sceptics who have held the wheel have an epiphany. Sometimes you can actually see the penny dropping by the expression on their faces. Thing is if you spin the wheel really slowly the forces just are not present. And so the argument goes round and round - just like the bicycle wheel. The faster you spin it the stronger it gets. To me those who insist countersteering is the only way to turn a motorcyle are missing out on as much as those who instist countersteering is a myth. Maybe my question belongs in a different thread away from the zealots and sceptics.

Here's the problem I have with saying gyroscopic procession is what leans a bike.

To start: Every action has an equal and opposite reaction. (we all know newton's third law)

So you spin the front wheel up and it balances itself in a strait line (as shown by gyroscopes spinning while only one side is supported)

You do the tire "trick" in the link you provided, spinning wheel, you turn it left it wants to lean right. Your theory, and one that I've read before on this site, is that the tendency of the spinning wheel lean right when twisted left is actually what is making the bike lean. (In fact some have said that at highway speeds the gyroscopic effect is the main force that leans the bike) So this theory works like this. You turn the bars left, the gyroscopic effect leans it right. You want to stand the bike up, from a lean right, you turn the bars right the gyroscopic effect leans it left. (am I on point?)

My problem with this is newton's third law. I read it to mean this. Back to the spinning wheel held in your hand example. You turn the spinning wheel to the left, the gyroscopic effect cause the wheel to tilt right with an equal amount of force that you applied by twisting.

If that is the case, and I'm not sure it is which is why I'm posting this. If when you turn the wheel to the right, it exerts an equal amount of force to lean, then the same thing is happening to the front wheel on your motorcycle.

You twist the bars to the left, that force is redirected by the wheel to a lean right.
If that leaning force is equal to the twisting force you applied, then an analog would be simply to pick the bike up by the bars while sitting still. With that in mind, the force I have to apply to the bars to pick the bike up from a 30 degree lean while sitting still in my garage is vastly greater than the force I need to pick the bike up from the same degree of lean while rolling down the road.

So my point is, maybe the gyroscopic effect provides some torque to the lean angle of the bike, equal to the force that I applied to the handlebars. But since the force I applied to the bars is no where near sufficient to lift the bike from it's 30 degree lean, I have to surmise that the majority of the torque is provided by the outsteering of the front wheel caused by countersteering.

My other reasoning is that turning the bars causes a moment gyroscopic torque, but that moment ends once I stop turning the bars. But my change in lean angle doesn't stop until I straiten the bars. I turn the bars a split second to the left, but hold that turn for 1/2 a second while the bike transitions from left lean to right lean. What's causing the bike to lean for the majority of that 1/2 second when I'm not actively turning the bars? IMHO it's the ousteering of the wheel, not the gyroscopic effect.

This is how I think about it anyhow, and I may be wrong..
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Boon Booni screwed with this post 06-19-2013 at 09:58 AM

06-19-2013, 09:41 AM   #708
Jim Moore

Joined: Dec 2001
Location: Jax, FL
Oddometer: 11,195
Quote:
 Originally Posted by Rucksta Stand beside your bike, left hand on the left grip, right hand on the grab rail and move the bike forward while maintaining full left lock.
It turns left because it's no longer a two-wheeled inline vehicle. You've created a tripod, so it's no longer germane to the countersteering discussion.

Quote:
 Originally Posted by Rucksta To me those who insist countersteering is the only way to turn a motorcyle are missing out on as much as those who instist countersteering is a myth.
Sorry, no. It's the only way.
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Jim Moore
-Turkish
"Your post was, as you noted, 'Pure f*****g gold' "
-Hawk

 06-19-2013, 09:47 AM #709 windmill Beastly Adventurer     Joined: Feb 2008 Location: Kent, Washington State Oddometer: 3,833 If I'm on a 2 wheeler and push on the right grip, I go right If I'm on a 3 wheeler and push on the right grip, I go left. Whats the question? __________________ "Take care, sir," cried Sancho. "Those over there are not giants but windmills".
06-19-2013, 06:58 PM   #710
joexr
Banned

Joined: Jan 2011
Oddometer: 2,720

Quote:
This is the best and most comprehensive post of the entire thread.

06-20-2013, 11:23 PM   #711
vortexau
Outside the Pod-bay

Joined: Feb 2008
Location: Just off the Warrego, S.E. Queensland
Oddometer: 1,511
Quote:
 Originally Posted by farmerstu perhaps an inmate would care to try this experiment i just thought up and report back. rig a steering stop so the bars will not turn past dead straight in one direction. lets say can turn left only. next put an electronic protractor on the bike to determine true vertical have a helper hold the bike true vertical while the rider gets moving. rider attempts left turn report back with results
Something quite similar-

No B.S. Machine

Quote:
 The Correct Brothers It shouldn't be alarming to me that riders still question how to steer their motorcycles but it is. Apparently, even after 90 years when it was first observed by the Wright brothers some confusion remains on this subject . Yes, their first engineering attempts were as bicycle manufacturers. The very observant brothers, determined that tandem-wheeled (one wheel in front of the other) vehicles countersteer. That was and still is correct. The Solution Make a bike that has two sets of bars. One set as normal, the other set would be solid-mounted to the frame so they were not connected to and did not rotate the forks. This, as my theory went, would answer the question. And it does. Dirty Exceptions Before I go any further I want to address off-road motorcycles. An off-road motorcycle will easily steer by pressing down on the inside peg, and in conjunction with shifting the upper body mass, will go over pretty easily . Still not what I would call good control but it can be done fairly efficiently. Again, I am not a true tech guy, but it occurs to me that the small contact patch on knobbies or dual sport tires plus dirt bike steering geometry (which is not intended to provide an enormous amount of stability at speed) contribute to the reasons why steering results from weight shifts to the degree it does on a dirt bike. No B.S. At this writing, we have run nearly 100 riders of all experience levels on this double-barred bike. It has made believers out of every single one in the actuality of countersteering of course. Even at speeds of no more than 20 to 35 mph, no matter how much you tug or push or pull or jump around on the bike, the best we saw was that the bike wiggled and became somewhat unstable. Did it turn? Not really. Would it turn at higher speed? Absolutely not. Could you avoid something in your path? No Way. Could anyone quick turn the bike? Hopeless! The best result was one of my riding coaches. He got into a full hang-off position and was able to persuade the bike, by jerking on it, to start on a wide, wide arc in the paddock at Laguna Seca, a piece of asphalt that is about 500 X 800 feet. Like turning an oil tanker ship, start at noon and be on the turning arc at around 1:00 PM. It wasn't smooth and it wasn't very effective. We now call this bike "The NO BS Bike". There are no doubts in anyone's mind after they ride it that they have been countersteering all along. No doubts. You can hear riders who believed in the body steering method, laughing in their helmets at 100 yards away, once they get those solid-mounted bars in their hands and try to body steer the bike. They just shake their heads. No B.S.
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06-21-2013, 05:29 AM   #712
Goran69
MNE

Joined: Sep 2008
Location: Montenegro Europe
Oddometer: 816
Quote:
 Originally Posted by hippiebrian How is this mind fest still going on? All this emphasis on countersteering. Rid a motorcycle? Don't stay in a straight line? Guess what, you're countersteering. Period. Laws of physics. The real practice, as I've said before, about taking a curve is looking through it. Turn your head. Practice that. Slow down. Turn your head. Accelerate through the curve. That is all there is to it. Doesn't need 120+ pages to explain.
+1..that would be it.....nothing more

 06-21-2013, 06:20 AM #713 KX50002 NooB, my ass     Joined: Mar 2012 Oddometer: 770 For those who think you can steer by leaning without countersteering... Try riding a bike with locked up steering head bearings, my son recently bought a 1986 Yamaha FZ6 the steering head was almost completely locked in the center position. I took it down the sreet in front of my house and almost had ta lay er down! I think it's so subtle sometimes you don't even realize you're doing it. __________________ SOTGMOTT Some Of The Gear Most Of The Time
06-21-2013, 06:37 AM   #714
PFFOG
Richard Alps-aholic

Joined: Aug 2005
Location: Western NY, further from NYC than 6 entire states
Oddometer: 1,398
Quote:
 Originally Posted by Goran69 +1..that would be it.....nothing more

+2

Look where you WANT to go!!

I was at an off road down hill bicycle race last weekend, basically a motocross using gravity as the engine, these guys navigate deep ruts , loose rocks, roots off camber slopes, tight turns and jumps at speeds of 45 mph.

When they get kicked off line by any of the above, how do they know how and what kind of input to put into the bars?? They are looking where they want to GO, and practice, practice, practice fined tuned their REACTION (note I didn't say cognitive actions).

YES if you turn a single track vehicle you counter steer, but at some point you then turn into the turn, it magically happens, without thought and explanation and has been done for a little over a century and a half.

Enough talk, go ride and become an expert at counter steering.
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Maritime Alps and Vosges

Richard

06-21-2013, 06:44 AM   #715
Jim Moore

Joined: Dec 2001
Location: Jax, FL
Oddometer: 11,195
Quote:
 Originally Posted by joexr This is the best and most comprehensive post of the entire thread.
Yes, because adults and ten year olds learn in exactly the same manner. Or some of them do, anyway.
__________________
Jim Moore
-Turkish
"Your post was, as you noted, 'Pure f*****g gold' "
-Hawk

06-21-2013, 12:50 PM   #716
lnewqban
Ninjetter

Joined: Jan 2012
Location: Florida
Oddometer: 240

Quote:
 Originally Posted by joexr Your # 2 is backwards. If you turn left the bike will fall right.
You are a practical rider, just try it.

Quote:
 Originally Posted by Rucksta Has anybody figured out the geometry parameters that control the transition speed between steering and counter steering and what affects the overlap between the two? Even if you haven't figured it out it may be entertaining to hear some different theories.
That is something that anyone can find experimentally:

1) From total stop, balance the bike vertically, put both feet up on the pegs.
From that position, if you don't turn the handlebar, the bike will fall to either side.
Repeat and verify: the bike has no preferred side to fall onto.

2) From total stop, balance the bike vertically, put both feet up on the pegs.
From that position, turn handlebar all the way to the left (full lock), the bike will consistently fall to the left side.
Why?: You have moved the CG of the bike left and is now off the line that joins the contact patches of the front and rear tires.
That is steering for you, and will work for standing still and for low speeds.

[/url]

06-21-2013, 01:31 PM   #717
joexr
Banned

Joined: Jan 2011
Oddometer: 2,720
Quote:
 Originally Posted by lnewqban You are a practical rider, just try it. That is something that anyone can find experimentally: 1) From total stop, balance the bike vertically, put both feet up on the pegs. From that position, if you don't turn the handlebar, the bike will fall to either side. Repeat and verify: the bike has no preferred side to fall onto. 2) From total stop, balance the bike vertically, put both feet up on the pegs. From that position, turn handlebar all the way to the left (full lock), the bike will consistently fall to the left side. Why?: You have moved the CG of the bike left and is now off the line that joins the contact patches of the front and rear tires. That is steering for you, and will work for standing still and for low speeds. [/url]
Your #2 is backwards. I think you're forgetting what the rake and trail are doing.

06-21-2013, 02:56 PM   #718
DAKEZ

Joined: Mar 2007
Location: U-gene, OR.
Oddometer: 19,070
Quote:
 Originally Posted by lnewqban That is steering for you, and will work for standing still and for low speeds. [/url]

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Quote:
 Originally Posted by Dirty in all Think Im going to unsubscribe from this thread before my wife divorces me because Im in the garage acting out scenarios trying to settle an argument between me and myself.
“Watch out for everything bigger than you, they have the "right of weight"
Bib

06-21-2013, 03:07 PM   #719
rbrsddn
3banger

Joined: Oct 2006
Oddometer: 2,165
Quote:
 Originally Posted by DAKEZ

This thread keeps delivering on a daily basis!

 06-21-2013, 03:22 PM #720 the Pheasant Gnarly Adventurer   Joined: Jan 2008 Location: Old London Town Oddometer: 372 Yup, the thread that keeps on giving. Seems to me there are a few people missing its point. Which is not to convince unbelievers that countersteering is fact, but to point out that learning to countersteer actively ie. to use what might seem like excessive countersteering to accentuate steering response is a useful thing to do. It gives the rider greater control, especially at higher speeds and when wanting to make rapid directional changes. True for me. Don't believe in countersteering? Try the technique. You'll like what it does even if you don't accept the reasoning behind it.

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