Hiding battery in airbox / Lithium batteries

Discussion in 'Airheads' started by ywouldi, Dec 3, 2012.

  1. Donkey Hotey

    Donkey Hotey De Jo Momma

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    I'm not going to draw free-body diagrams for you. If you can't figure out that the shear is being taken out between the battery and the tray, no diagram will convince you. Yes, the battery's CG is above that mounting plane but, rocking of the battery turns into a large vertical translation with only the tiniest lateral translation. If the nuts are tight, that lateral translation is zero.

    This is how people can have a $100K seat of Nastran and get hyper-accurate, yet incorrect results.

    Perhaps explain how a rubber strap over the same tray would hold the same battery in place? The rubber strap has no meaningful resistance to bending. Is it magical, non-bending rubber?
    #21
  2. boxerkuh

    boxerkuh Been here awhile

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    Love the discussion. I have spend a great deal of research on this matter. I am not wanting to subject my daily rider to early burn out so I am keeping the airbox in place. What I have done so far is shaped 2 US license plates by hammering them and enclosing the current batter box. That allowed me to remove the side covers and to have a "custom" look. The "hammering" procedure was a workout and an experience in off self, one plate I did on concrete and the other on wood. It's different. When I change the rear subframe to a /5 short I will hang the battery underneath the seat in a custom box. It will be out of the way, it will be an open look, which will work well.

    Bottom line for you will be "What do YOU like" and what you can afford. Making it yourself might be the cheapest way, but all the suggestions given to you will work and are different....even the one you don't like from Boxer Metal under the frame (BTW: I considered it, but was not willing to sacrifice the centerstand).

    My brother runs a Lithium battery on his 2010 K 1200GT and he loves it... technology...


    Compromise....it is what it is.... compromise....:lol3
    #22
  3. Big Bamboo

    Big Bamboo Aircooled & Sunbaked

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    OK, I tried to read that whole thing, really I did, but I see only specs on cold weather starting. Does anyone know how well the lithium batteries handle heat?
    #23
  4. Boxer Metal

    Boxer Metal Mad Scientist

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    All corners of this aluminum plate are cracked?
    #24
  5. Jon-Lars

    Jon-Lars Jon-Lars

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    I am only concerned about the mounting of the bolt to the base. It's fixed on one end, weakened by the cut threads, and highly stressed. There is no way to alleviate the side load with the threaded end fixed that way.
    #25
  6. boxerkuh

    boxerkuh Been here awhile

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    We live in South Carolina and have aweful Summers. My brothers bike is K bike with a full fairing and it is in the middle of the thing. I would say, that you are good to go with summer concerns. Should not be an issue....
    #26
  7. WRC51

    WRC51 Long timer

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    This is in an old BMW, I dont think the force from from the engine will rock that battery too much.:wink:
    #27
  8. DiabloADV

    DiabloADV Semi-Occasional

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    Yeah...if mine accelerates (or brakes) hard enough to snap the battery mounts off, I will be the happiest airhead around.

    Those mounts aren't going anywhere. Just because you can come up with a conjectural scenario for failure doesn't mean the actual scenario will lead to failure.
    #28
  9. Jon-Lars

    Jon-Lars Jon-Lars

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    Of course not.
    Poor design leads to an increased chance of failure, not a guarantee of failure.
    The failure mode I have in mind isn' sudden but rather eventual cracking and separation after subject to vibration and off-axis excessive loading.
    #29
  10. Other Bob

    Other Bob Been here awhile

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  11. crazydrummerdude

    crazydrummerdude Wacky Bongo Boy

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    Seems like Jon-Lars has a hidden beef with bmweuro.. :dunno

    I don't personally like the look of the battery in the airbox area, but there are plenty more statically and dynamically loaded members of the bike that, if structural failure happened, would lead to a much more catastrophic result than a battery slightly cocking over... and BMW designed them! :lol3
    #31
  12. Jon-Lars

    Jon-Lars Jon-Lars

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    Not really.

    I am not making a personal attack.

    I am criticizing the part, which, by the way, was invited by the poster.

    How about being the first poster to explain why the extra threads are helpful and necessary?
    #32
  13. DiabloADV

    DiabloADV Semi-Occasional

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    FWIW...I agree. Ideas, parts, modifications...they are always open to critique here. That's how we learn and get better. We just need to always keep it technical and not personal.

    I've changed plans on my build a few times by lurking and reading about problems that I hadn't considered.

    For one...I won't be running intake pods. :deal
    #33
  14. Boxer Metal

    Boxer Metal Mad Scientist

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    I don't feel attacked at all. The extra threads are there because that is a part we use for another product and it works fine. The battery is recessed in the tray almost a 1/4 and inch and isn't going anywhere.:D
    #34
  15. Boxer Metal

    Boxer Metal Mad Scientist

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    I don't want to derail this thread but I would like to say that all of the products I offer are because folks like yourselves have asked over time does anyone make.........The great thing about ADV is the diversity. As much as I have helped with various tech questions over the years I too have learned a lot. Lets keep picking, poking and educating.
    #35