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Shimano Biopace????(7 posts)

Shimano Biopace????grande
Jul 28, 2003 5:12 PM
So I was a the swapshop at the dump and was staring at what looks like a late80s to early 90s Schwinn Worldsport bike there. 12 seconds later is was on my roof. Got home and was stripping it to the salvagable stuff thinking how i'd turn it into a commuter. the rear wheel was bent the chain was rusted. All cables were crap. I then checked the crank. At first look it looked warped, oblong. But its not bent latterally at all. Its actually in good space. An oblong crank? Am I halucinating?
Yup, ya got a Biopace nmbyker
Jul 28, 2003 5:18 PM
No hallucinationWalter
Jul 28, 2003 5:21 PM
BioPace was an "innovation"marketed by Shimano starting sometime in the mid80s. I'm not sure when they discontinued it.

It was supposed to, as I recall, produce a pedal stroke more in line with natural leg/foot motions. More powerful stroke, faster spin, less injury prone, blah, blah, blah.

Most who tried it switched back to standard chainrings but I recall a few who really liked it. Pops up in vintage discussions every now and then. No collectible value though the few who do like it are often looking for spare rings as Shimano dropped it pretty cold.
Its fans are hardcore, thoughjtolleson
Jul 28, 2003 8:13 PM
If you've ever met one. Blah blah blah "efficient" blah blah blah "no dead spot" blah blah bla "I really miss it."

Assuming you got a good deal and this is a fun backup toy, why not? Part of me has always wanted to ride a biopace crank and never has.
Its fans are hardcore, thoughboyd2
Jul 29, 2003 3:44 AM
The first time I rode a Biopace bike was in College. I borrowed my housemates MTB to ride around one weekend. I wrecked it and as I was checking it out afterward I noticed the oblong chainrings. I thought I had done it!
re: Shimano Biopace????mapei boy
Jul 29, 2003 9:56 AM
I still have a biopaced bicycle hanging in the garage - a late '80's Cannondale MTB stiffie. The biopace rings are disconcerting when spinning high revs, because at certain points during the cycle it seems to want to "rush." But when you're hammering up a hill at low revs, you do get more leverage at those moments where your stroke is at its weakest In short, a mite strange, but biopace is not quite as terrible as the naysayers on this board make it out to be.
Biopace for suregtscottie
Jul 29, 2003 2:40 PM
I have a set on my late 80's Miyata. It actually is fun to ride. I seem to be able to power up a lot faster but when you are at high speed and try to spin fast I get kind of a bounce going that doesn't happen on my MTB or my other road bike so I assume it is the biopace rings that do it.

Any thoughts on that?!?!