[ST] Countersteering

[Bare <barenekd@xxxxxxxxxxxxx>]

Not a whole lot of info about the actual experiment, but I'm not sure I get 
what he's trying to prove - that you actually have to turn the bars to make 
a motorcycle steer?

I'm interested in any comments.  Thanks!

John in NJ
'01 BRG ST


	Keith's trying to demonstrate that you can't steer a motorcycle by all these other methods people claim to use to steer their bikes, like weight shift, loading the pegs, and other crap.
	Let me fill you guys in on a little of my background. I have been riding for about 45 years, raced dirt, flat track, scrambles , motocross, enduros, crosscountry, hare & hounds, etc, for 25 and have done extensive pavement work, road racing, track days, canyon carving, owning and riding everything from BSA Gold Stars to Honda 929s. I was a fast amateur, winning a fair share of my races, so there is a fair bit of experience speaking here. I figured out countersteering back in the early '60s before anyone ever made any mention of it, or gave it a name. It worked for me and I never thought much about it. Then, in the late '70s, it started popping up in the "How to ride" seminars as the new Riding Schools emerged. I went to Keith Code's California Superbike School in '80 and he as taking about it then and trying to explain why it works. He went through all this centrifugal force and precession and a bunch of crap that some engineer idiot laid on him that didn't make much sense, but, he was right, it does work. The reason it works is very simple. Centrifugal for makes a bike want to go straight. Simple enough, and that's about all you need to know about it, other than, the faster you go the more centrifugal force there is because the wheels are rotating faster so it takes more effort to turn the bike.
	Since we've gotten to the point where we want to turn, what is it that is going to do the job? Basically the requirement is to get the bike to lean into the direction we want to go. How do we do that? We can put all our weight on one peg and it will push that side down, very inefficiently, I might add,  as there is very little leverage between the peg and the CG of the bike, but it may slowly lean that way and start to turn. Or we can hang our butt off the side, and that will react somewhat faster, but there certainly isn't going to be much accuracy in the bank angle or of the turn radius, and then how do we get it upright again? Shifting our butt to the other side probably won't work, and we will most likely bust our butt. 
	The only way a motorcycle or any single track vehicle truly turns is by countersteering, except at very low speeds where banking isn't required. And the reason it works is that when you countersteer, the initial reaction for the bike is to turn in the opposite direction (adverse yaw to the flying types), because the point of contact of the front tire shifts to the side that you steer toward. This tends to make the bike want to fall over in the opposite direction. When it has fallen to the point that the angle equals the radius you want, you pull the bars back to balance that angle by moving the contact patches of the tires in line with the center of gravity (coordinated turn). It holds that line until you move the handlebars to the inside of the turn, making the bike want to lean the other way and straighten up. This is where "losing the front end" can occur as you are trying to turn the bike a little more sharply and there is no excess traction available. So, in reality, you countersteer both entering a turn and exiting it.
	The only thing hanging off to the inside achieves is to keep the motorcycle more upright as it goes through the turns, keeping more rubber on the ground. It will reduce the amount of countersteering required, but does not eliminate it. For those who don't think they countersteer just need to pay more attention and analyze what you are actually doing with your hands, because I can guarantee you that you are putting pressure that you don't think you're doing. Maybe instead of pushing the inside bar, you're pulling the outside bar. But nonetheless you ARE countersteering, or crashing a lot. Or go ride Keith's No B.S. Bike and see how well you fare.
	So, putting this brief narrative into perspective, you can see how countersteering actually works and why it is necessary to the operation of single track vehicles 
Bare






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