Counter-steering
An exercise in feedback management
By: James R. Davis
We all seem to know what counter-steering is, from a practical point of view, because we must use it to guide our moving motorcycles. But I'm of the opinion that far too few of us understands it beyond lip service - that is, beyond a catchy phrase such as 'push right, go right'.
I suggest to you that if that was all you had to do to use counter-steering your very first turn would end in a low-side. That is, if counter-steering was merely pointing the front wheel away from the direction you wanted to go, your bike would be too unstable to ride.
Consider: You remove the rider and replace him with a mechanical linkage that absolutely controls the steering angle so that you could (remotely) instruct it to turn the handlebars 1/4 inch to the left (analogous to pushing right) in order to turn right. That bike would make a quick jaunt to the left and then immediately fall over on its RIGHT side.
Why? Because counter-steering is much more about pressure management than controlling steering angle. It is about adjusting the amount of steering input you provide in order to reduce feedback pressure caused by trail (called 'restoring force'). That is, when you 'push right' you are adding steering pressure that causes the bike's front-end to turn to the left and centrifugal force then causes it to lean and turn to the right. Your trail results in a corrective force (that 'restoring force' I just mentioned) which is greater, by far, than the steering input you provided. And that pressure increases the tighter the turn becomes - radically. It then becomes your job to ease off your input so that the pressure remains only the modest amount you initially input. If you did not ease off, then the feedback pressure would endlessly rise as the bike made an increasingly tight right turn to the point that your lean angle would become more than the bike's tires could support, or until you hard dragged some metal on the ground - in either event, resulting in a low-side.
That mechanical linkage I earlier described only changed the steering angle, it did not measure feedback pressure nor did it ease off in an attempt to stop the increasingly tight turn. Your mind does that with ease!!! Your hands feel the feedback pressure and your muscles ease off in order to maintain the same amount of pressure.
Sure, push right starts the bike going to the left, but your objective is to go to the right without going so far to the right that the bike loses traction. In order to do that you must ease off the amount of pressure you are providing as steering input.
Gently press right in order to gently turn right, harshly press right in order to 'flick it' over into a right turn, absolutely push right (no 'give') in order to low-side on the right side. Your input is both directional ('right') and pressure ('gently') and of those it is the pressure component that is controlling.
To make a turn tighter when you are already in that turn, you merely apply slightly more forward pressure on the inside grip.
Copyright 1992 - 2024 by The Master Strategy Group, all rights reserved.
http://www.msgroup.org
(James R. Davis is a recognized expert witness in the fields of Motorcycle Safety/Dynamics.)
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