Scientific American pseudo-Biopace 1894

A post from Sheldon had a link to Harper's Weekly (digitized, unlike
the cursed Scientific American), so I looked through my folder of
scans for something to repay him.

Aha!

Sheldon often mentioned a fondness for BioPace oval chain rings, whose
design tries to change the effective gearing during the pedal cycle.

Oval chain rings themselves are old hat, but here's a short Scientific
American article from June 16, 1894 at the bottom of the page, which
shows that there's more than one way to skin an oval or elliptical
cat:

http://i19.tinypic.com/871vsxi.jpg

The idea is that the crank bends outward as you push down, turning a
165 mm into a 175 mm with more leverage just when you need it.

Even better than Biopace, the harder you push down on the curved crank
arm, the more it straightens out and lowers your gearing--perfect for
hill climbing! The springiness also absorbs vibration--doubtless the
cyclo-cross riders will be using it next season. Available only from
F.F. Ide Manufacturing on Ide bicycles--hurry before everyone else
gets one for Christmas.

Makes our modern hollowtech cranks and squabbles about stiffness look
pretty primitive.

Sheldon mentioned that the print in these scans is almost illegible
because it's so small. They're dreadful scans, but the size should be
reasonable.

This two-column scan (cut from three in the original) should be at
least 8 inches wide. If not, either you want a bigger monitor or else
you need to find out how to display the image full size. In Explorer,
move the mouse down to the lower-right corner and left-click on the
icon that appears to enlarge things. Some Linux and Mac users may
suggest their solutions.

Cheers,

Carl Fogel

On Dec 15, 5:41 pm, wrote:
A post from Sheldon had a link to Harper's Weekly (digitized, unlike
the cursed Scientific American), so I looked through my folder of
scans for something to repay him.

Aha!

Sheldon often mentioned a fondness for BioPace oval chain rings, whose
design tries to change the effective gearing during the pedal cycle.

Oval chain rings themselves are old hat, but here's a short Scientific
American article from June 16, 1894 at the bottom of the page, which
shows that there's more than one way to skin an oval or elliptical
cat:

http://i19.tinypic.com/871vsxi.jpg

The idea is that the crank bends outward as you push down, turning a
165 mm into a 175 mm with more leverage just when you need it.

Even better than Biopace, the harder you push down on the curved crank
arm, the more it straightens out and lowers your gearing--perfect for
hill climbing! The springiness also absorbs vibration--doubtless the
cyclo-cross riders will be using it next season. Available only from
F.F. Ide Manufacturing on Ide bicycles--hurry before everyone else
gets one for Christmas.

Makes our modern hollowtech cranks and squabbles about stiffness look
pretty primitive.

Sheldon mentioned that the print in these scans is almost illegible
because it's so small. They're dreadful scans, but the size should be
reasonable.

This two-column scan (cut from three in the original) should be at
least 8 inches wide. If not, either you want a bigger monitor or else
you need to find out how to display the image full size. In Explorer,
move the mouse down to the lower-right corner and left-click on the
icon that appears to enlarge things. Some Linux and Mac users may
suggest their solutions.

Cheers,

Carl Fogel

Hi, Carl, I'm using the Firefox browser and Ubuntu Linux 7.10.

By moving the cursor to the bottom left of the screen one gets the
option to magnify the text.

Kind regards.

Lewis.

*****