>
> >On a sunny day (Fri, 01 Dec 2023 07:32:21 -0800) it happened John Larkin
> > snipped-for-privacy@997PotHill.com wrote in snipped-for-privacy@4ax.com: > >
> >>> >>
> >>>Automatic bike transmission concept is wild and spiky—and could be a big shift
> >>>formatting link
> >>>
> >>>Looks fun to me... Maybe for the eldery?
> >>>Or in SF hills?
> >>
> >>Gearing dosn't overcome conservation of energy. Non-gorilla-athletes
> >>here zigzag uphill to reduce the slope and effectively create a
> >>super-low gear. Or, lately, use an e-bike. It's cool to see a mom with
> >>two kids in a trailer climbing a 10% grade.
> >>
> >>We have one street near here that tops 36%, but I've never seen a bike
> >>on that one.
> >>
> >>I suppose a generator-converter-motor transmission would be too heavy
> >>and inefficient.
> >>
> >>The holy grail in mechanical design is a really good
> >>continuous-variable transmission. We EEs are lucky to have switching > >>regs.
> >>
> >>My Audi has a 6-speed dual-clutch transmission that switches between
> >>two parallel gear trains, odd and even. Something like that could work
> >>on a bike.
> >
> >It all made me think of the DAF:
> >formatting linkSome cars have them, but they tend to be unreliable.
My dad had something like that on his Minneapolis Moline combine. The moveable parts of the pulleys were connected by an arm that would move them to keep belt tension consistent. I don't remember how the operator made the variable speed part change speed. The unit might've been made back in the late 1940s. There wasn't anything complicated about it. There was a 3 speed manual transmission ahead of this. The variable speed gizmo let the operator fine tune speed. MM called the unit a Uni Harvester or something like that.