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Evaluation of brake reaction times on a motorcycle

Discussion in 'Research, Studies, and Data' at netrider.net.au started by TonyE, May 2, 2012.

  1. Evaluation of brake reaction times on a motorcycle
    http://www.promocycle.com/documentations/studies-eng/evalfrein_e.pdf

    Summary
    Brake reaction time (BRT) of motorcyclists was measured on a sample of 1,181 subjects, using stationary real motorcycles coupled to a computer. The test sample was drawn from among public visitors to the 2002 Quebec City Motorcycle and ATV Show and the 2002 Montreal Motorcycle Show. Participation was done on a voluntary basis.

    The mean BRT obtained by the group of test subjects, all classes combined, was 0.463 seconds. When the subject waited for the signal with fingers already poised over the brake lever and foot positioned over the brake pedal, the mean measured BRT was reduced by 0.154 seconds compared with the procedure in which the subject waited with fingers wrapped around the handlebar and foot placed flat on the footrest.

    At 100 km/h, an increase of 0.154 seconds represents an increased braking distance of 4.28 metres. The age of the subject, the sex of the subject, and his or her experience of off-road riding, of distance ridden during the previous three years or of automobile driving had no significant bearing on the results.

    The unique factor influencing BRT in any significant way is the position of the fingers and foot while waiting, or covered mode.



     
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  2. Good post mate.
     
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  3. #3 Ljiljan, May 2, 2012
    Last edited by a moderator: Oct 24, 2015
    Wonderful. I remember flux made a similar statement (though not a researched result) based on video analysis.

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  4. According to Spokes it takes 1.5 seconds to react and brake.

    See http://www.spokes.com.au/take-control/

    I am sure this is based on the same good research as "68 times more likely" or whatever the latest figure is.

    Tony, do you know who exactly are Spokes. I know they are featured on VicRoads site in the past and I assumed were part of them but I note a Geelong address.

    Personally I think the reaction time quoted is probably a driver time based on putting the phone down and making sure the latte is back in the cup holder before performing any sudden manouvers
     
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  5. Spokes is the TAC's official website arm for motorcycle issues.

    It purports to be a resource site for motorcyclists.
     
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  6. Well some of its resources appear a tad dodgy.
     
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  7. just remember that this is a simulated test where the subjects know that they are being tested for reaction time and so are ready to brake thus these times should be on the fast side of the bell curve. However, the point is still valid in the the brake will be applied quicker if your fingers are already on the lever.

    One point that they did miss I think is that anticipation will always be faster than reaction and this is where the more experienced ride might have an advantage provided s/he is alert.
     
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  8. Good roadcraft should see you at least covering your brakes for a braking manouvre wherever the spider senses get tingly. For example, I've never ridden through Acland or Fitzroy streets in St Kilda without the brakes covered...
     
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  9. I spend the vast majority of my urban riding time with at least two fingers resting lightly on the front brake lever. I know from experience that I can brake to near lock up with those two fingers if I really have to. I can't do it repeatedly but for most emergencies once is enough :D.
     
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  10. I find it interesting the difference between brake covered and not, is so small.

    Roughly half a second reaction time to something you're expecting, something you know you're sitting there with the express purpose of being tested on, is around about what I'd expect, actually a little on the fast side of what I'd expect.

    Roughly one and a half seconds to respond to something completely unexpected, again, seems to be at the long end or slow end of what I would expect, but certainly not outside the norm. I have watched people in the real world take more than two seconds to react to the car in front suddenly stopping or people walking onto a pedestrian crossing ... Without tracking those people down and asking them, you have to wonder if they were reading a text message, or in the middle of a sneeze, or trying to find the glowing end of the cigarette that just dropped in their lap, or something. How long does it take to check the speedo, glance at the fuel and temp gauges, and then check the mirror before having a good look in front of you? If you look in the mirror and see something that attracts your attention, how long might you spend watching it before you looked forward?
     
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  11. Never quite understood this as most of my riding is hill stuff. I found that riding with brakes covered can lead to nasty situations where you have applied brakes but have not properly rolled off the throttle and hence braking capability is considerably reduced. My preference is to have a hand position that in the process of reaching for brakes rolls the throttle off by default.
     
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