That is actually kind of cool
That down tube is going to get folded in half where the seat stays attach.
I keep watching the video seeing the top tube flex? When he actuates?
100%
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Well, it was that, or have the collar around the seatpost slide up and down as the seatpost pivoted, I guess.
Gotta love these shows, there’s always some new contraption that reminds me of the best film from the 70’s - Gizmo! - that showed all the early inventors in the 20th century trying to create the Next Big Thing.
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Loading the down tube like that is standard for all the single pivot bikes like Starlings and so on
Just pick a geo and stick with it
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Yeah but there is the additional support of a complete front triangle with rigid joints in those cases
I’m sure it’s fine if you make the walls really thick
The front triangle is rigid, the dropper drooper locks
but the lower pivot doesn’t
I don’t think the upper pivot locks either
Just the extension mechanism
The top tube is definitely vestigial. Without the top tube, it could be a fat tired Dutch bike.
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Dropper drooper locks, but you’ve got free pivots at the bottom of the ST and top of the ST instead of welded joints. So if the downtube wants to flex at the chainstay attachment, the main thing resisting the “main triangle” becoming a quadrangle is the bending strength of the downtube. Yeah it’s a welded rigid joint up at the head tube, but the geo is such that the top tube has to flex to allow the seat drooper to droop - that’s why the top tube is so flattened/ovalized, so I don’t think it provides a ton of strength in this case.
I get that if you consider everything to be rigid this isn’t any different than a full-susp bike that mounts the shock to the DT, but I don’t think you actually can make that assumption with this frame.
I’m not assuming it’s as rigid as a normal frame, but we already know the failure mode involves localized buckling, and since dude has been building full suspension bikes for a couple years I think he has a good sense what he needs for the down tube. We can see from the Double Drooper that’s he’s taken this into account with the stays attaching to a gusset like part.
its just the 2024 version of this.
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Btw I knew you’d reply about the pinned joint statics and was patiently waiting for Vietnam posting time of day
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Pinkbike comment of the day: Looks like a Marino
I do like the shock placement for more water bottle storage.
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Seems really progressive for an air shock too
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