close

Privacy guaranteed - Your email is not shared with anyone.

Question about braking over bumps

Discussion in 'Mechanical & Technical' started by trav87, Aug 1, 2012.


  1. trav87

    trav87
    Expand Collapse

    1,297
    0
    Trophy Points:
    366
    Location:
    Lebanon, OR
    There was a situation where a rider had to hard brake just after hitting a decent size bump (close to 3 or 4 inches) on a r/r crossing. The bump was bigger than expected due to the panels that transition from r/r to pavement flop about and dip down with weight on them.
    The two shiny ones in the picture below.

    [​IMG]

    This picture shows how little distance between the r/r and light, as well as a different view of the panels in the road.

    [​IMG]

    As a result the front end washed out during braking due to what I would think as the suspension being unsettled and not being able to maintain full traction while braking. Judging by the amount of skid marks present, this isn't the safest intersection...
    How would someone explain the change in suspension and traction forces to say an attorney, insurance agent, or transportation official who doesn't have any motorcycle background, or any common sense for that mater lol
    The rider isn't looking to get rich, but rather to get the problem with that crossing fixed, and maybe the damages to the bike covered.

    It seems Euro bikes are spendy to fix :scared so I will stick to the Jap bikes :popcorn:
     
  2. rusty nail

    rusty nail
    Expand Collapse

    743
    28
    Trophy Points:
    178
    Location:
    Sandy Oregon
    There are a of of skid marks that start before the tracks. So it looks like people are trying to stop for a light that they see too late. The light in the picture looks like it is easily seen. Anything there not obvious from the picture?
     
  3. Ryanthegreat1

    Ryanthegreat1
    Expand Collapse

    1,965
    1
    Trophy Points:
    518
    Location:
    Olympia
    What is the speed limit on that road?

    I hate to burst your bubble but that stop looks like it could be made no problem even at 45mph.

    But then again I don't ride the latest and greatest race track suspended bike with fancy brakes. 96 VFR would be my worst stopping steed. I could see a race bread bike being stiffly valved and sprung in such a way that could cause a rather harsh bump.
     
  4. Ryanthegreat1

    Ryanthegreat1
    Expand Collapse

    1,965
    1
    Trophy Points:
    518
    Location:
    Olympia
    It does suck that rail crossings are so rough sometimes but that is to be expected. I am always up off the seat for crossing them and watching for the nasty holes.

    It does like like that is 3-4 car lengths from the crossing to the stop line. Hard to tell with the camera lens. So 40.5' to 54' to stop.
     
  5. Nathan

    Nathan
    Expand Collapse

    1,018
    0
    Trophy Points:
    366
    Location:
    Seattle, WA
    I automatically slow down when riding over crossings, but I speed up when I see a yellow light.
     
  6. PeteN95

    PeteN95
    Expand Collapse
    Moderator
    Staff Member

    12,198
    54
    Trophy Points:
    1,278
    Location:
    Mukilteo, WA
    You should reduce braking force as you cross questionable surfaces, then re-apply as you return to good traction. Same goes for lean angle through a turn, reduce, then lean back in.
     
  7. trav87

    trav87
    Expand Collapse

    1,297
    0
    Trophy Points:
    366
    Location:
    Lebanon, OR
    Yes, there is about 3 car lengths, speed limit is around 45 I think. The incident occurred when two cars panicked braked for the red light, thus reducing that 40 to 50 foot braking zone down to around 20'. Picture doesn't show it, but those tracks are at the end of a corner, and the lights aren't clearly visible, not to mention the first picture is taken around the end of the intersection for a different light. Video footage of the crossing shows the majority of the r/r's transition panels are loose and malfunctioning.
     
Loading...
Similar Threads Forum Date
Engine braking questions Motorcycle Talk May 23, 2012
braking question Motorcycle Talk Oct 15, 2011
A few questions about dealerships. Motorcycle Talk Feb 24, 2016
A swing arm question Mechanical & Technical Dec 29, 2015
R6r Fork Question Mechanical & Technical Dec 27, 2015