Durham, aka Bullseye, went to a more drastic extreme with this idea a few years before Biopace. I forget the product name but their chainring was too ovalled to use as part of a multiple chainring system, was made in a range that STARTED at about 54 teeth. I rode the Davis Double one year in the mid-70's in a group with a guy who was completely sold on these football-like rings; as the day wore on he was more and more envious of the rest of us in the group, looking longingly at our 42/24 low gears! David Feldman
> Message text written by "Rick Miller"
> >I have an early 80's touring bike equipped with Shimano Bio-Pace rings.
> I've rarely seen them used and wonder what their purpose was? I suppose it
> should be obvious but I prefer the round rings.<
>
> Bio-Pace rings were just another one of Shimano's me-too deals. A
> couple years before it was SunTour with their OvalTech rings. SunTour
found
> out just how unpopular they were and dumped them about the time Bio-Pace
> came out. Shimano stuck with them for several years.
> The idea is that the ring has a longer radius like a bigger ring
> where the most power is exerted on the pedals is the greatest and the
> shortest where you can apply the least power.
> I agree, they are a bad idea and like most everyone else, went to
> round rings as soon as possible.
>
> Jim
>
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