Custom crash barz advice/critique PLEASE

Discussion in 'Equipment' started by Widtsoe, Apr 30, 2013.

  1. Widtsoe

    Widtsoe Add throttle

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    I am planning my first ADV ride and I need experienced opinions on this design of crash bar. I am having to build this myself because none are available for my bike (not many take this bike off the tarmac).

    I have never ridden (or crashed) a bike with crash bars, so I know very little about what makes a good design and what does not. I have frame and axle sliders, but I felt that it would be a good idea to add crash bars, a skid plate and better bark busters. I have a spare sub frame that I plan to weld mounts for bags too, but that's another story.:evil

    THE PROJECT
    Instead of wasting a bunch of metal, I decided to mock up a design made from one inch wood dowels. Instead of welding crash bars to my frame, I decided to use some tube clamps used in off road cars and trucks (not pictured). I feel that it would be a good idea to weaken (drill) the chrome moly tubes near where they attach to the frame so that they will be the first thing to bend versus my frame. I tried to style the thing to loosely follow the looks of the bike.

    Any advice would be greatly appreciated.:ear



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  2. NesquikNinja

    NesquikNinja Long timer

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    :lurk:lurk
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  3. squish

    squish Out of the office.

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    Hmm
    I'd set out a thick blanket and lay the bike over and see what's the first point of contact, then work out from there.
    I don't think I'd have anything that would bolt to, weld to or otherwise transfer crash forces to the frame.

    There's a bash plate made for this bike out there somewhere, it's under $250 last time I looked.

    I'd think about getting replacement non carbon fiber panel for the Belt guards and the exhaust heat shields and fr fender.

    That point as you have it designed will be a weak point and in the worst case could slice the living hell out of you if you landed on it wrong.
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  4. bomber60015

    bomber60015 Anatomically Correct

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    From a strength standpoint, bends are much better than welds.
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  5. Widtsoe

    Widtsoe Add throttle

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    Yes, I agree. I have a friend with nice tube benders, but for the mock I just wanted to rough in a design....I was unable to bend the wood rods.:D I just hope that he can bend the tubes at those radii. I wanted to keep the overall size of the CB small and thus weight. Thank you!
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  6. Widtsoe

    Widtsoe Add throttle

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    :ear
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  7. MK96xj

    MK96xj 100% Seat Time

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  8. Jim K.

    Jim K. Long timer

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    The advice to lay the bike down & see what touches first is excellent. The only thing I would add is that the bike probably won't be at a stop when it goes down. Try & triangulate the strongpoints so there will always be one or more lined up with the direction of travel. When it hits the ground, there will be force vectors along the length of travel, not just straight down. Also, try to avoid sharp bends/angles. You want the bike to slide & scrub off speed on it's side, not dig in and pitch on to the other side or somersault, end over end.
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  9. Widtsoe

    Widtsoe Add throttle

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  10. Widtsoe

    Widtsoe Add throttle

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    Thanks Jim, sage advice. Thinking about what you've stated and considering the above "Strada" crash bar, it attaches to the other side under the triple and seems to have those attributes you mentioned.
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  11. squish

    squish Out of the office.

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    Carbon fiber is not very flexible, ABS plastic is slightly more flexible, and cheaper to replace.

    Lots of crash bars mount to places that you really don't want to transfer the force of a crash to.
    But Ducati frames are very fragile, as are their engine casting, broken swingarm mounts are not uncommon.

    If you bolt to the frame bolt somewhere, where the force of the crash is not between two hard points like in the middle of a span of tubes or even where two tubes meet.

    Build something into the crashbar that's designed to fail and absorb some of the force of the crash.Not unlike how they notch the back side of hand control levers.
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  12. Widtsoe

    Widtsoe Add throttle

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    Thanks Squish.:clap
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