Culprit Bicycles is showing a triathlon bike at the Taipei Cycle Show that has disc brakes, but no seat stays. Called the Legend, this bike is aimed fair and square at the triathlon market as there is no way it will ever be UCI legal.
"I am now in prototype stage after one year of dreaming, and six months of drawing, redrawing and 3D," said Culprit general manager Joshua Colp.
Colp claims the bike to be "the first disc brake triathlon bike in the world," although it's still a prototype.

An unusual look for a triathlon bike: disc brakes and no seat stays
Colp said he plans to have rideable versions by June, with production in five sizes by the end of the year.
"The bike is UCI-illegal, triathlon-specific. I have applied for a structure patent on the design," he said. "The bike was developed in cooperation with Trigon Cycles and I have worked closely with them to develop a new stem, aerobar and seatpost. The new Trigon aerobar/stem will be sold on the aftermarket by the end of the year as well."

Hydraulic lines route through the stem. Note the absence of a stem preload cap
Colp claims the absence of seat stays allows for some vertical flex in the frame that could keep triathletes' legs fresher for the run.
The rear has 135mm spacing for road discs, but will come with alloy adapters to bring it down to the 130mm road standard. The frame can also work with TRP TTV brakes, Colp said.
The complete bike will come with either SRAM Red, Shimano Di2 Ultegra or Shimano mechanical Ultegra. No prices have been announced.

Culprit claims this Legend prototype to be "the first disc brake triathlon bike in the world"