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Visual Conflict of Interest
Especially when Accelerating

By: James R. Davis

There are times when your eyes show you what you expect to see and other times when they show you something else entirely. This tip attempts to demonstrate why you need your mind to be 'in the present', and why you need to actively interpret what you see instead of believing what your eyes are telling you.

For most of your riding history you have trained yourself to respond to visual input with almost 'reaction' speeds, to not delay responding in any way because at highway speeds you cover a lot of ground in very short order. Delays (internal debates about what you should do) can result in unthinkably harsh consequences.

Take as a real world example of this the fact that many of us, certainly myself included, cover our front brake lever whenever we are riding at faster than parking lot speeds. We know that it takes, on average, about one full second to recognize an unexpected threat and to decide to react to it, and then it takes additional time to begin doing something - like reaching for and squeezing that brake lever. We cover the front brake lever because that will shave off at least 1/10th of a second of reaction time and, as a consequence, it effectively provides us additional stopping distance between our motorcycle and that threat. Indeed, 1/10th of a second at 60 MPH provides us a life saving extra NINE FEET of stopping distance.

We train ourselves to REACT as quickly as possible to that visual input. We also use the time from the moment we start to squeeze that brake lever to decide how hard to squeeze it. That little decision is made AFTER we begin doing something about the threat, not before. Humans are damned smart after all.

So what could possibly be wrong with that scenario? Not a thing when you are travelling at highway speeds - it is a life saving learned behavior.

So then what is the purpose of this article? Well, you are not always traveling at highway speeds when you notice a threat and at very slow speeds, particularly if you are accelerating, your visual input can lie to you.

Consider ... you are stopped behind a vehicle which is also stopped at a signalled intersection with a red light. The light turns green and both you and the vehicle ahead of you begin to move. That is, you are both accelerating.

What your eyes show you is that the car ahead of you is pulling away from you - the gap between you and it is widening. But what your mind is telling you is that you have rolled on your throttle and your body is telling you that you are accelerating. So far, so good. But going back to your mind for a moment, your experience is such that you EXPECT the gap between you and the vehicle ahead of you to be getting smaller OR YOU ARE LOSING THE RACE! That, in turn, causes you to roll on the throttle even farther.

The two second rule remains just as valid at 5 MPH as it is at 60 MPH. When you were stopped at the light you were very close (relatively) to the back of the vehicle ahead of you. As both vehicles begin accelerating the gap between them MUST WIDEN in order to provide that two seconds worth of space. But your mind, if it is not 'in the present', if you are simply going through the motions without active thoughts controlling your behavior, expects the gap to get smaller. You are not a 'loser' of races, after all.

So, there is a time when both your eyes and your mind misinterpret a widening gap and prior experience causes you to INAPPROPRIATELY respond by rolling on even more throttle. But that is essentially no big deal, not particularly dangerous. It becomes dangerous when that vehicle then unexpectedly hits its brakes! Then your eyes are in a conflict of interest position. They show that the distance between you and the vehicle you are following is narrowing - just as you expected because you have rolled on that throttle. And instead of REACTING as quickly as possible to avoid the collision, a delay occurs as your mind gets out of racing mode and into survival mode. Covering the front brake lever saves you 1/10th of a second when you need it, which is significant if you have distance to stop, but you have, by rolling on that throttle, eliminated (shortened) the gap - there isn't two seconds of space there as there should be, and you end up biting the rear-end of that vehicle with your front wheel - and the pain begins.

Get and maintain that two second following distance IMMEDIATELY, especially when starting from a dead stop.

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(James R. Davis is a recognized expert witness in the fields of Motorcycle Safety/Dynamics.)

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