Casey the parts cleaner forgot to put the chainrings back on the Univega's crank arm, so I had to do it.
The rings are Biopace, Shimano's computer designed shape, rather than round, and they're meant to give more power to the wheel when you push down on the pedals.
The rings are Biopace, Shimano's computer designed shape, rather than round, and they're meant to give more power to the wheel when you push down on the pedals.
Above are the Univega Biopace chainrings now attached to the crank arm.
The shape is also supposed to be easier on our knees over time, but I read that Shimano botched the marketing of Biopace when they cast doubt on the design's ability to perform in competition as well as normal round chainrings.
So while they put them on most bikes in the 80's or so, you don't see Biopace around anymore.
When you have trouble with your knees these things matter, you see... Remember to stretch those thigh muscles after every ride!
The shape is also supposed to be easier on our knees over time, but I read that Shimano botched the marketing of Biopace when they cast doubt on the design's ability to perform in competition as well as normal round chainrings.
So while they put them on most bikes in the 80's or so, you don't see Biopace around anymore.
When you have trouble with your knees these things matter, you see... Remember to stretch those thigh muscles after every ride!