Tri-bars explained

CHRIS SIDWELLS

Cycling Legends - GREG LeMOND

A brief history of tri-bars and why they make such a difference to a cyclist in a time trial, so much difference that they are used universally today.

The idea of fitting an attachment to standard dropped handlebars to give a more aerodynamic riding position was born in the world of ultra-distance cycling and was developed by somebody with a skiing background.

Ultra-distance racers seek comfort as well as speed. In 1984, cyclist Jim Elliot rode to fourth place in the 4,800km (3,000 mile) Race Across America (RAAM) on a bike with centrally placed arm rests on its handlebars. That year's race winner, Pete Penseyres, adapted Elliot's idea, and in 1986 he competed with a handlebar attachment that allowed him to ride with his forearms supported and his hands extended centrally in front of him.

At the same time Boone Lennon, the US ski team coach from 1984 until 1986, was thinking about the way cyclists rode, and bringing his knowledge of the aerodynamics of skiing to bear. He believed that bringing a cyclist's arms in line with their body, as well as flattening their forearms, like downhill skiers do in a tuck position, would make cyclists more aerodynamic, and therefore faster. So he developed the first clip-on tri-bars.

In 1987, one year after Penseyres  won the RAAM, Boone Lennon patented a design. His invention was simple: an aluminium tube bent into a U-shape and clamped to the top of a bike's existing handlebars. Elbow pads were added to the handlebar tops; the rider crouched down, rested his or her elbows on the pads and held the forward part of the U-shaped tube with their hands.

The new position brought the rider's arms within the silhouette of the body, thereby reducing the frontal area dramatically. Additionally, the action of bringing the elbows nearer together rounded the rider's shoulders, smoothing air-flow over their back. Then a final bonus came from ergonomics. A cyclist holding tri-bars in a tuck position has the weight of their torso supported by their skeleton, rather than by their arm muscles. The new braced stance allows the cyclist to roll forwards, reducing the frontal area further while requiring less energy to maintain the position. 

Lennon's clip-on handlebars were produced by the ski equipment manufacturer Scott. Triathletes were far more enthusiastic about the clip-on handlebars than cyclists, so by the time LeMond used them first in the 1989 Tour de France they were already known as tri-bars. The name has stuck ever since.

This original tri-bars didn't look much, but they changed time-trial bikes for ever. Many variations of Lennon's basic design followed. Athletes and coaches experimented with new positions to try to maximise the possibilities that the new braced tri-bar position allowed. Saddles were pushed further and further forward as the riders tri-bars got lower and lower.

To accommodate these changes, the basic geometry of the bikes changed, with time trial specific frames having much steeper seat angles and shorter top tubes. Gear shifters were also mounted on the tri-bars.

But tri-bars were still an accessory, something that could-be attached to a standard dropped or bullhorn handlebar with a few bolts. Then in 1991 the French bicycle product company Corima produced the first integral tri-bar, incorporating both outboard hand position, where the brakes are located, and the new TT bars in one unit. Later on the brake levers were incorporated in the same unit.

Although basic design remains unchanged today, some manufacturers are starting to make handlebar and frame units integrated and developed into one flowing design. The resulting products are aerodynamically superior and aesthetically pleasing.