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Every motor needs a turbo
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for any newcomers...there was a debate earlier today about motorcycle steering. i say while completely in a turn, your front wheel is turned in the same direction as youre turning. others say it is turned in the opposite direction of the way youre turning, throughout the whole turn. me n maynard have a test set up for saturday which will prove this ($50 to the lucky winner) but i found some really good facts that supports my thinking. as i said before...motorcycle steering is typically explained as to what your actually doing to turn...not actually whats happening on the bike. figured id share one that explained it well.

mods if you dont like this then take it down. i dont see what the big deal is though to discuss something thats a part of our bikes.

thanks,
enjoy

taken from www.physicsforums.com

this may help you understand that the earth is indeed round.


Motorcycle Dynamics:
There's been lots of controversy and dim-witted flame wars on rec.motorcycles concerning how a motorcycle steers. I myself have given this lots of thought, done many calculations, tried some experiments, and here in layman's terms is what I think.

When you initiate a turn by pressing the bars in the opposite direction (i.e. countersteering), the bike responds by leaning. This is due to the `outtracking' effect. Basically, you steer the bottom part of the bike out from under the centre of mass.

As the bike leans, gyroscopic forces cause the forks to turn into the proper direction. You don't notice this because the handlebar movement is very small. All you notice is that a constant pressure to the left causes a lean to the right and subsequently a turn to the right. In effect, the handlebars end up turning in the direction opposite to that in which you are pushing them. But this depends upon the spinning of the front wheel. That's why it doesn't happen in the same way when driving very slowly. You can verify this by rigging up some kind of long pointer from the handlebar centre. Others have done this. The gyroscopic effect can be verified by playing with spinning bicycle wheels.

Rake and Trail:
To understand the importance of motorcycle/bicycle steering geometry, a good place to begin is with a simple caster wheel as found for example on grocery carts. This is a system that has trail but no rake. (Trail is the distance that the point of contact of the tire with the road trails the intersection of the steering axis with the road.) Basically, the wheel pivots to the necessary direction to follow the direction of motion. A similar system does not work on a single-track vehicle because such a vehicle leans when it corners. Try the following. Take such a wheel (say from an office chair), and lean it to one side, pushing it down to mimic the effect of the vehicle's weight. You will notice that it tries to flip outward, turning into the turn. In other words, if a motorcycle had such a geometry, you'd have to counter-steer very strongly just to keep it leaned over in a turn. Now orient the caster the 'wrong' way so that the trail is negative. Lean it and weight it. You'll notice that it tries to turn out of the turn. This suggests that steering would be neutral if trail were zero. This is correct, but zero trail is not an option since we want some of the self-stabilizing caster effect. The way around this is to tilt the steering axis back from vertical. The angle of tilt is called rake. Take a wheel on a steering axis with no trail. Now rake it backwards. Immediately you have trail equal to the tangent of the rake angle multiplied by the wheel's radius. It turns out that for neutral steering, this is too much trail. The optimum is about 2/3 this amount. On a motorcycle, this is achieved by moving the forks ahead of the steering axis. On a bicycle, the forks are curved forward.

Example: My motorcycle has a rake of 27.5 degrees, and a wheel radius of 13.5 inches. With no fork offset, the trail would be 13.5" x tan 27.5 = 7". A 2.5" offset reduces the trail to 4.5".
 

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I agree with you, when I'm completely leaned over at the track I can feel that the wheel is with me in the turn. And no it isn't sliding lol
 

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Armed law abiding citizen
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I have no idea what the fuck all that was. But I got the muffler on the 955i to drag on the ground the other day. :) I rule more than a gixxer. :laughing:

 

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Pathological Thrill Seekr
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No hater here, just enjoying an interesting debate. :thumbsup :cheers

All you notice is that a constant pressure to the left causes a lean to the right and subsequently a turn to the right. In effect, the handlebars end up turning in the direction opposite to that in which you are pushing them.
I think you said it all right there :jester
 

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Si Vis Pacem Parabellum
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I have no idea what the fuck all that was. But I got the muffler on the 955i to drag on the ground the other day. :) I rule more than a gixxer. :laughing:

Did you drop it? Is it possible to drag muffler without dropping the bike? What rubber are you running on that guy Dave? I think I can see a Bridgestone B, but not sure.

Back to the thread, I'll take that bet too, the tire is NOT going with you midway through the turn.
 

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Serious inquiries only
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No mod deleted my thread, I did. I put up a funny in the funny forum and you turned it in to a serious debate!

A little bickering here and there, but it was starting to turn into a monkey poo fling contest :biggrin:

I might speak for myself, but I don't think anyone hates you.
 

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Lovin this Twin
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Isnt the question here, how fast are we going?

A uturn in the parking lot, or a slow turn, then yes I agree

Fast sweepers? uh,,,total dissagreement

Debate on....:2cents:
 

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6Teen Cycles
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If your turning fast enough the tire will be pointed to the outside of the turn. I would take that $50 bet all day long.
 

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I have no idea what the fuck all that was. But I got the muffler on the 955i to drag on the ground the other day. :) I rule more than a gixxer. :laughing:

All that means is your suspension isn't adjusted and you're going to crash soon :lmao: squid :laughing: :cheers:
 

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Lovin this Twin
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Heres a simple test, do a fast sweeper and take your left hand off the grip.
Tell me what your right hand is doing? pulling or pushing ?
 

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you shouldn't really be holding on tight anyways... A better test... go through that sweeper at the track with finger tips, if you can't you have poor body position. When I'm at the track I initiate the turn with body position and counter steering. When I'm fully leaned I feel the clip-ons either slightly straight out or point into the turn
 

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Enjoying Life!!
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Isnt the question here, how fast are we going?

A uturn in the parking lot, or a slow turn, then yes I agree

Fast sweepers? uh,,,total dissagreement

Debate on....:2cents:
:thumbsup
 

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CLSB's Florida Chapter.,
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the real debate

will a plane on a treadmill take off if the front forks are slid up to compensate?
 
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