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Thread: So how good are you,....at braking?

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  1. #1
    Nickname: Droid
    Join Date
    Jun 2005
    Location
    Green Bay, WI
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    2,352

    So how good are YOU,....at braking?

    I found a braking distance chart for motorcycles (on a law firm website). The chart listed a ?standard? of 134 feet to stop from a speed of 60 mph for all bikes and riders. That seemed to be a very optimistic, unreal short distance so I decided to test it myself. I mean, a 60 mph stop in 134 feet calculates to an .89 G-force stopping effort, as an ?average? value for motorcyclists. Below are results from my somewhat accurate braking test session. I set up a 150 foot braking lane out on a rural road, running east/west, and measured with a long tape, I marked off the start, and 150? mark with paver bricks. The road was smooth, clean, grippy aged asphalt. After setting up my markers 150' apart, I paced off the distance to use as a reference from the bike to the marker when I stopped. The 150' distance took 53 strides (I have a 30? inseam), so that equaled 2.85' per stride. After each stop, I'd dismount and walk the number of strides from the leading edge of the front tire to the ending brake marker. Only two of the 12 stops were slightly longer than the 150' braking lane.

    I got my bike up to an indicated 65 mph, which I know on my bike is just slightly over 60 mph, and made sure the speed was steady before I got to the braking marker. At the marker I applied both brakes as best I could. I noted when the ABS activated, which was probably 75% of the 12 stops. Each stop left a very definite stripe from the front tire on the road for the entire stopping length. But no lockup and sliding. I also felt the bike definitely squirmed around a bit but also self corrected. Here we go:

    TEST DIRECTION DISTANCE SPEED (approx) NOTES
    1 East 165.5 60 1st test and helped establish my marker start point
    2 West 140.0 60
    3 East 142.9 60
    4 West 151.4 60
    5 East 152.1 60 ABS cycling of the rear brake, over braking on rear
    6 West 134.4 55 Speed was definitely lower at start of braking zone
    7 East 154.2 60
    8 West 150.0 60
    9 East 141.5 60
    10 West 141.5 60
    11 East 157.7 60 Attempted stop with no ABS actuation
    12 West 137.0 60
    AVG 147.3 My speed was only estimated as read on speedometer

    The tire marks on the pavement also helped me determine I was applying the brakes 12' to 21' before the brake start marker. I adjusted my noted stop distance by adding the early stop distance to the ending position. So even though this was all estimated, the repeated efforts and variables are minimal enough to determine some consistency. Some other notes, my 94 R1100RS has ABS, and the Telelever front suspension with designed in limited squat during braking. No matter how hard I apply the brakes the steering geometry remains consistent which helps to control the bike. By the end of the testing I could sense a slight headache due to the G-loading of the stops. The final points are unless you test and practice your braking, you'll never know what you can safely achieve. So, for my average of 147' at 60 mph, if I add one second reaction/application time (88' for 60 mph) to a real world stop, my best average TOTAL stopping distance for 60 mph stops would be 235 feet!! Eye opening to say the least!

    So, going back to the chart I found on the web, I feel the distance of 134 feet as an overall average for motorcycles (regardless of bike style, CG, wheelbase, braking system, ABS or no, training, practice) in general is unrealistic. I have been riding for 42 years, and been teaching the MSF programs for over 20 years. So my focus on riding skills is perhaps a bit stronger than the average rider. Perhaps if I went out and repeated this exercise to hone my skills further, or included an assistant to evaluate my technique and more accurately measure my braking distance I could get closer to that 134? average. But more telling, is that in this test instance, with repeated attempts, under conditions I controlled, I was not easily able to match the supposed average. I controlled many of the variables in this test. But in the real world the variables are far greater. That to me says the chart I found is speculative at best, and can be argued in a legal sense for inaccuracies. But I wonder how many riders or lawyers would simply apply the chart data in a court setting, as representative of an average Joe rider.

    My point here is not in any way to say "Hey, look at me and what I did!" In fact I'd like to know how others do at testing their braking ability. The point is to evaluate what you yourself can really do on your bike, practice it and find out before you put yourself in situation calling for more than you may be capable of. I see SO many riders following other vehciles WAY more close than thier real braking ability could ever save their ass.
    Last edited by ANDYVH; 06-19-2013 at 06:49 PM.

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