Bolt Crash Bars to Motor / Good Idea ?

Discussion in 'Land of the Rising Sun: ADV Bikes from Japan' started by Kaw4Life, Sep 21, 2009.

  1. Kaw4Life

    Kaw4Life Busted Adventurer

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    Most companies that make crash bars for the F800GS use the available pre-drilled/threaded holes that are on the motor. Tourtech makes the point that theirs do not. Anyone else think that a hard dump will bust/crack the motor mount locations?

    Thoughts.
    #1
  2. WoodWorks

    WoodWorks House Ape

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    Well, there have been several crashes involving bars that mount to the motor. None of them, AFAIK, have caused any damage to it. Maybe the engineers who designed those bars calculated the stresses involved and concluded that the risk was negligible. And it seems that they were correct.

    David
    #2
  3. Kaw4Life

    Kaw4Life Busted Adventurer

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    Thanks Dave !

    My thought is that BMW would not have put them there if they would cause problems. The SW-MOTECH bars mount to the front set of holes as well as the other 4. I am thinking this will be quite strong.

    :johntm
    #3
  4. EnderTheX

    EnderTheX Dirt Rider

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    These engines are meant to be a stressed component of the frame.

    Besides, it is much better to put a shock through the recommended mounting holes than directly into your case!
    #4
  5. Kaw4Life

    Kaw4Life Busted Adventurer

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    Lost me on that one man, the recommended holes are in the case. The factory BMW bars mount to the motor case. As far as I can tell only one company mount to the frame (Tourtech).
    #5
  6. Motoriley

    Motoriley Even my posing is virtual

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    Looks like a solution to a problem that doesn't exist. Has anyone heard of this "problem"?
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  7. Kaw4Life

    Kaw4Life Busted Adventurer

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    That is effectively the question I am looking to answer. Has anyone ever damaged these connecting points by bolting crash bars to them.
    #7
  8. RAD800

    RAD800 Been here awhile

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    If you do manage to dump your bike that hard just let the Ambulance people and your insurance company sort it out. :ricky
    #8
  9. jodyz121

    jodyz121 Mostly Harmless . . .

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    Wunderlich and Touratech bolt to the frame.

    Touratech bolts to the frame near the footpegs.

    Wunderlich bolts to the center stand mount.
    #9
  10. subybaja

    subybaja Long timer

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    The 800's been out how long?
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  11. WoodWorks

    WoodWorks House Ape

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    Almost two years now. November of 2007, to be precise.

    David
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  12. Threewheelbonnie

    Threewheelbonnie Long timer

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    Never seen an F-twin go down, but engine bars ruined a trip for an airhead owner. He passed us, then went down on a micro climate under an autobahn bridge. Once we'd picked him and the bike up there was oil all over. The engine bar had ripped a stud out of the bottom of the motor and left a crack that may or may not have been weldable.

    I don't know who made these bars, but they showed rather limited thinking. These bars were designed to protect when you dropped the bike at zero speed, all the fixing points were fine in compression. Once the load was in tension/shear, the weak point was the casting.

    Personally, I'd go for bars that'll fold/up rip off in an 80 mph highway crash but will save the tank at zero speed. The current trend for massive engine bars is the issue to me as much as where they mount. If you must have the massive/survive at 80 mpg type, I'd want to be sure the mount would take the loads, which to me says frame mount.

    Andy
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  13. subybaja

    subybaja Long timer

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    Pretty short sample time, considering that the small percentage that get bars are further divided by the different bar brands out there...
    But then, my KLR was made in 1967. (almost)

    :dunno I dunno...seems goofy to me to bolt the protection onto the thing being protected. Kinda like mounting your car bumper to the fenders.
    #13
  14. Kaw4Life

    Kaw4Life Busted Adventurer

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    Understood, not looking for high speed protection. Looking for the 15 mph protection. With a brand new 08 KLR at a LOW speed tip over cost about $800. The next day the SM-MOTECH bars came in. These are well designed for the KLR and have proven themselves more than once.

    I like the TT bars but am thinking they are going to get in the way. My knees go way forward.
    #14
  15. Motoriley

    Motoriley Even my posing is virtual

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    No engine bar is going to survive every possible scenario. In the past two years every F800 that has been truly ridden off road has been dropped. Almost every picture I've seen has shown some sort of engine guard.
    Where is the thread on cracked engine cases??? Lord knows BMW owners wouldn't be shy to complain...
    In other engine guard threads people have posted post crash pics. This fellow went down in third gear on asphalt.
    http://www.advrider.com/forums/showthread.php?p=10309523#post10309523

    Another asphalt crash

    http://www.advrider.com/forums/showpost.php?p=10723268&postcount=216

    As for drops on dirt there must have been thousands by now....
    #15
  16. Kaw4Life

    Kaw4Life Busted Adventurer

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    Well to sum it all up it would seem that most any bar will add to the betterment of the bike and rider. WoodWorks seem to have personal experience with this, I will take his word as one of an authority. If you can hit the pavement and not brake the mounting point then I am covered.

    Thank you all for your input.
    #16
  17. Maddaddy

    Maddaddy Greg

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    I have confidence in my adventure spec crash bars which bolt through the frame to the engine.

    The points that they are mounted and the way they are connected along with the extra bushing would disperse the energy from a pretty hefty fall.

    I think that if the engine did crack, it wouldn't matter as they would be pouring me out of my helmet.

    The boxer engine has too many places where a crash torques the crash bars, hence a broken engine mount. My friend broke a head bolt in a simple fall from the protection designed to protect the head itself.
    #17
  18. Law Dawg (ret)

    Law Dawg (ret) Been here awhile

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    Frame, engine, or combo mount...all is moot. If you hit hard enough to damage the mounting points on the engine, you would have certainly hit hard enough to damage the mounting points on the frame (or combo). Either way the bike is toast. I put on Adventure Spec bash plate and crash bars (well designed BTW) not because I was going to begin trials riding or crash testing. I put them on to protect mainly from lower speed excrement occurrs stuff. I don't expect them to hold up to a boulder bash or high speed get off and if they do...bonus!

    There are more than a few real life examples here of no kiddin' crashes that crash bars reduced the damages. There are also many pics of the F800GS in the "napping" position on trails with crash bars allowing the rider to just pick it up and ride away. Maybe some pics? Y'all know who you are.
    #18
  19. WoodWorks

    WoodWorks House Ape

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    Here you go, Law Dawg. On the Great Divide Trail this July. By the time we got to southern Colorado, the poor thing was just a little pooped.

    [​IMG]

    The Givis are great for the post-nap lift. They work just like the jugs on the Boxer engine do, keeping the bike well off the ground for an easier pickup.

    David
    #19
  20. Ride-a-lot

    Ride-a-lot Been here awhile

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    Where do you get the 80 Miles Per Gallon crash bars. Sounds like a good feature, I'll buy some! :D
    #20