I like the SWAM crank and the FaceFace seatpost. Extra points for a sense of humor.

there's been a number of prototype grad school projects and usually you can tell the person really isn't super-bike savvy [aside from the grad students who developed that new THM stem]. This guy is definitely an exception.

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wovebike.com | Wove on instagram

That bar setup would be ideal for an event like the Leadville 100.

I like the idea of a 4x6 gearbox. IMO, the advent of electronic shifting should have really encouraged more use of the front derailleur. Maybe something like a 3x11 where the front and rear are setup to "synchro shift" to provide ~26 unique gear ratios with relatively tight spacing. That said, the internal gearbox idea is a bad idea unless you're trying to go for low service and high reliability. The frictional losses intrinsic to planetary gears are quite high.

Internal gearbox, in my opinion, is a great future. Could be quite adaptable, aero. Just needs a bit more development

I'm still sold on the expanding cog/chainring system - prototype using sram etap wireless batteries...

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wovebike.com | Wove on instagram

CVT with V belt drive is the way to go IMHO. Infinitely variable (within limits of course), with auto shifting/ratio adjust.

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"

That system definitely has enormous potential. The smartest way to execute it, IMO, is to have rechargeable cyclindrical batteries oriented about the axis. Assuming you use a worm drive mechanism to expand/contract the chainrings, you would have stepless gear changes (along with perfect chain line and chain tension). Since you wouldn't have to worry about chain line you could totally enclose the front chainring with just rearward facing entries/exits for the chain.

Perfection - ST crowd sourced prototype?

(and to the previous poster, this idea is cvt. Belt drive requires high tension so it's high friction).

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wovebike.com | Wove on instagram

Basically, we're talking about something like this for both the front and rear: http://www.wavetransmission.com

As the front expanded the rear would contract and vice versa. The chain line would be perfectly straight and chain tension would be constant. This is not fundamentally different than the CVT arrangement you suggest. The only real difference is that chains are way more efficient than belts!

Just estimating from information gleaned from various patents (expandable chainrings are a surprisingly old idea!) a 400% gear range should be possible.

My experience with CVT's is with mechanical plant in air conditioning applications. Static pulleys need to be swapped out to change fan speed (for example). And pulleys only come in specific sizes so the possible fan speeds are stepped, much like the cassettes we have on our bikes. Before the common usage of VSD's (variable speed drives) that change the driving motor speed, to affect a speed change in the fan, there were adjustable pulleys. You could either adjust a manual set of pulleys to provide the one constant speed you needed, or alternatively, have adjustable in motion pulleys that could open and close the pulleys, resulting in changing the effective diameter of the DriveR and DriveN pulleys, to change the speed of the fan, with a constant motor speed. With the advent of VSD's adjustable in motion pulleys have gone out of favour. Given the cost of air conditioning energy consumption and the near universal use of V-Belts in the past, I'd assumed the efficiency was at least reasonable. I'd have to go back to my notes (which I can't be bothered doing) to confirm the actual losses.

While the changing chainring diameter you have, with a chain, has efficiency benefits (I think) it still has a stepped approach and off the top of my head, I'm thinking that might be somewhat limiting. It is intriguing however. I need to think more about this.

Thanks for the link. It's certainly cool

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TriDork

"Happiness is a myth. All you can hope for is to get laid once in a while, drunk once in a while and to eat chocolate every day"