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  1. #51
    Ozzie Ozzie Ozzie Peter Aawen's Avatar
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    Quote Originally Posted by pegasus1300 View Post
    Actually Peter I don't see where this would be any worse then the 40# hitch weight we run when we pull a trailer. You could just get a hitch from BRP or any of the accessory people put a plate on it and get a plastic bin like he shows in th pictures and as long as you keep to the 40# it should be ok.
    I can see what you're saying, and even agree with your suggestion re just getting a hitch & putting a plastic bin on it; but if you look at the pics in the first post, it appears that the trunk wasn't intended to be fitted at all like the OE hitch, but rather carried out further behind the Spyder on longer arms; arms that the axle passes thru at the swing arm end, which extend forward of the axle & are then braced underneath the swing arm. So while the 'OE hitch' works (??) as an extension of the swing arm with a 40# weight being applied on the end, you really have to think of this suggested trunk holder as a Lever and Fulcrum system - sorta like this:

    When you put a 40 # weight directly on the tow ball of an OE tow hitch, that weight is still held fairly close to the rear of the Spyder & exerts little leverage on the hitch & swing arm itself - it's more of just a weighted swing arm extension. However, when you put the same 40#'s of down force onto the end of a 3 foot long Lever/beam that's been slid in above where the tow ball would normally be positioned; then allow it to pivot on the axle itself as a Fulcrum; & apply it's extended leverage force under the swing arm anywhere in front of the axle (as seen in the bars you can see in the pics of post #1); then even tho the weight itself (or the downward force/effort applied) isn't any greater than that applied onto the OE hitch, the leverage that weight/force affords due to the length of the lever or effort arm (which is admittedly only really a little longer than the length of the normal hitch, but it's there, and it only takes a little extra length to create a force multiplying lever ) and consider where that weight is being applied ahead of the pivot (or fulcrum) at the axle & then enhanced by that load arm length by lifting under the swing arm somewhere ahead of the axle, would mean it has considerably more effect... IIRC the basic rule goes something like - 'If the distance from the effort to the fulcrum is greater than the distance from the load to the fulcrum, then the lever has a mechanical advantage' - given some measurements someone could probably even do the calcs to work out how much more the lift would be over the 40#'s of effort, but please, not me...

    And don't forget, because of how this 'considerably multiplied lifting force' will be cantilevered out the back behind & above the pivot point/fulcrum of the rear axle & then applied to lift under the swing arm before being transferred into the similar cantilever effect formed by the swing arm & shock on the frame, then the lifting force transferred thru the frame by even just that same 40#'s of load would likely be uncomfortable on the steering & braking at best, downright dangerous at worst!

    But that's just my musings...




    Ps: it doesn't really matter if the load/leverage is ahead of or behind the Fulcrum, the principal is the same, & the compounded leverage will be lifting the front of the Spyder - just tested it both ways, & albeit with an unladen Spyder & no ryder/pillion aboard, it didn't take a great effort to lift the front wheels using a 3-4ft long lever.... Those wheelie rollers mentioned earlier in the thread might've been a great idea??
    Last edited by Peter Aawen; 09-11-2021 at 08:19 PM. Reason: Ps:
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  2. #52
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    Peter, you 'muse' well.

  3. #53
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    But that's just my musings... Thank you Peter.
    Any kid who's ever played on a teeter-totter knows about leverage. I guess schools don't allow teeter-totters on the playground anymore.

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