Shimano’s Ill-Fated Biopace Validated in University Study

In an interesting turn of events, Shimano’s much-maligned Biopace chainring technology appears to have gained a new lease on life as a result of recent findings published from a recent study conducted at Université Joseph Fourier, in Grenoble, France.

Contrary the court of public opinion, researchers found that Shimano’s Biopace chainrings vastly increase a rider’s ability to maintain threshold power over standard and current elliptical chainrings. Biopace is a type of ovoid bicycle chain ring manufactured by Shimano from 1983 to 1993. The design was intended to help overcome the “dead zone” where the crank arms are vertical and riders have little mechanical advantage.

However, as recently brought to light, Biopace actually excels at engaging muscles in a more linear fashion, from hip to toe, encouraging a pedal stroke that actually works in concert with the body’s lymph system, facilitating faster lymph circulation.


For a time, nearly every Shimano-equipped mountian bike sported Biopace chainrings.



Poole and his researchers spent six months on their initial study, incorporating several different testing groups to reduce sampling error.

What does this mean? Without regular contractions of the leg muscles, lymph can’t return to the upper body readily, and collects in the lower legs, producing uncomfortable swelling, called edema. While pedaling with a non-Biopace chainring still facilitates lymph circulation, researchers were surprised to find that Biopace rings increased lymph circulation by a margin of 26-percent over other chainrings. From a performance standpoint, lymph represents a portion of the blood, meaning that if lymph weren’t returned to circulation through the action of muscles, blood volume would decrease.

“In simple terms, Biopace allows riders to flush lymph in a way that isn’t unlike the methods used by masseurs on professional racers after races,” explained Dr. Jéan Poole, lead researcher on the project. “The only difference, is that with Biopace, riders reap the benefits while they are still on the bike, allowing them to ride harder, for a longer duration.”

Specializing in the fields of sciences, technologies and health, the Université Joseph Fourier encourages post-graduate researchers to adopt projects that align with their own interests, leading a group of students with cycling backgrounds to revisit Shimano’s Biopace chainring technology and its effects.


By helping to increase a rider’s effective blood volume, Biopace allows riders to ride at their lactate threshold for longer durations, posing serious performance benefits.

Spurred by the recent increase in popularity of elliptical chainrings, researchers were keen to examine the differences between such current chainrings and their predecessors, namely Shimano’s Biopace, which never gained widespread popularity and was largely dismissed as a technological flop and a failure.

After being approached with the findings, however Shimano Inc. has expressed its intent to revisit Biopace.

“While we will take our time to evaluate the findings put forth by Dr. Poole and his team, we are very intrigued and will seriously consider incorporating Biopace options into our current road and mountain product lineups,” said Shimano Road product manager David Lawrence in a press release Monday.

Happy with the initial findings of their study, Dr. Poole and his team have already begun another round of testing to further validate their conclusions.

Shimano has also made public in the same press release that it has devoted a full-time engineer to the project who will reside in France and will pay close attention to the findings.

For the university team’s full report, click here.