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Downshifting During Emergency Braking
(MSF teaches an Unsafe practice)

By: James R. Davis



The MSF insists that you downshift while braking in their range exercises. Indeed, if you fail to do that your performance is reduced in the class.

The logic for this, they explain, is so that you end up in first gear when you come to a complete stop so that, if you need to then quickly start moving again, you can do so without loss of time.

This is simply specious thinking, in my opinion. It suggests, for example, that either you are always in second gear when you begin braking or that you are to downshift several times while braking, even in an emergency situation.

But there is an even more obvious flaw in that argument. The technique they teach is to downshift at the start of your braking effort. In other words, you are encouraged to take the time when you are moving at your fastest speed in order to save time when you are not moving at all - after you have come to a complete stop. (You would think that if you don't let out the clutch lever during multiple downshifts you will not have lost any time. Untrue. The reason is not because of engine braking conflicts. It's because of the distraction that interferes with braking skill performance.)

Most of you have heard my arguments for covering your front brake any time you are moving faster than you can run. In essence, my argument is that by covering your front brake lever you save yourself about 1/10th of a second in reaction time or, at 60 MPH, about NINE FEET of stopping distance as compared to not covering that lever.

Note, please, that again we are talking about saving time when the motorcycle is moving at its highest velocity. So, advice by the MSF to downshift at the start of your braking effort is tantamount to advocating that you give away braking time while the motorcycle is moving at its highest velocity.

There is, of course, another even more important reason that you should NOT downshift while emergency braking. It takes mental effort and focus away from what may well be a life saving concentration on controlling your motorcycle during an emergency braking maneuver - a distraction when you simply cannot afford any distractions.

It is my opinion that downshifting while braking CAN be safely done during any normal gradual stopping maneuver but should NOT be done in an emergency stop effort. The MSF training is misdirected and counter-productive to the extent that it fails to differentiate between those kinds of maneuvers and it leads to longer stopping distance and greater time to stop during an emergency situation.

Studies have convincingly shown that in order to stop in the shortest possible distance and the shortest possible time you must disengage the clutch fully at the time you begin to brake. Here is a link to one such study.

Here, for example, is a chart that demonstrates the effect that clutch usage had on 77 emergency braking stops performed by professional riders performed and documented by the Federation Motorcycliste Du Quebec in 2004:



You see that the greatest deceleration rate, fastest time and shortest distance all were the result of fully disengaging the clutch lever at the start of an emergency stop effort.

Get into the habit of downshifting AFTER YOU HAVE COME TO A COMPLETE STOP.

Copyright © 1992 - 2019 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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