General: Biospace Chainwheels??

I found them
in the back of a old bargain bin
in an old bike shop

Owner dint even know he had them
i figured it would be an interesting additon to my
road bike
but is it wise?

alo i only have two, the bigest one and the smallest
can i just use them
or can i put a regular chainwheel in the middle?

You shouldn't have a problem with them, but I don't think they ever really did all that much either. You shouldn't have a problem mixing them a round ring. I've even seen kids use them on fixed gears.

Posted By: upthemaidenI've even seen kids use them on fixed gears.

most idiotic idea ever.

it wouldn't. hahahahahah

i've tried it. it went from super tight to super loose.

I've always had a soft spot for Biopace. Many years ago, my father gave me his 1982 Lotus Grand Prix, which he upgraded at one point or another to Biopace. While I found the difference between a conventional chainring and a Biopace chainring to be subtle, I appreciated the experience and benefits it yielded.

Over the past few years, I have built a handful of bikes for my girlfriend, all of which have similar parts, geometry and fit. More recently, I built up a 1987 Cannondale with Biopace. After a couple 20 mile rides, over varied terrain, she said that she felt more fluid on the bike, especially when going up hills. I suppose part of this could be attributed to the frame material, but I think a lot of it had to do with the attributes of Biopace.

I'd say if you've got them, give them a shot. Just don't mix them with conventional chainrings as per Sheldon's article.

I have used them extensively on mountain bikes where all three chainrings are BP. I used these mountain bikes for single track and cyclocross. I believe that they do make a difference and technically the idea is sound, the reason they failed is because everyone says the world is flat and so it must be so. You may find that they fit your riding style. You can check out one of my mountain bike pics on the site with the original BP chainrings. This particular MB is a veteran of the Kenai Peninsula and Resurection Pass in Alaska and cyclocross in Washington state with the BP chainrings..
Give them a shot, I don't think they'd spin well, (but on the mountain bikes at lower spin rates they were great) and make your own judgement.

I think that 'bad for your knees' comes from people confusing them from elliptical chainrings/ovaltech chainrings, which were rotated 90deg in comparison to a biopace.

Had them once. Never again. I'm a big fan of spinning, and I don't find them helpful for smooth circles. Also don't like them on hills; I found it harder to keep my momentum.

Within several months, I switched to SR Roundtech rings at the time. SR also made oval rings called Ovaltechs (sometimes found on Suntour cranks as well) which were in between round and BioPace in terms of their profile. Rotor makes a much improved design called Q-Rings; if you get them tuned right (they need to be mounted to match your pedal stroke's peaks/valleys) they supposedly work quite well. They aren't nearly as extreme as oval chainrings, and there's better science behind them.

http://www.bentrideronline.com/reviews/qrings/qrings.html

i'm a nyc bike messenger and i've ridden biopace on a single speed for years. i find it smooth. i don't understand why some folks care if others ride biopace. if you think its shit, let me be happy on my shit. i do 200-250 miles per week on them.