The bicycles were distributed by Cervelo Cycles Inc. of Toronto.
They were sold from September 2012 through January 2013 for about $3,600 if sold with the P3 with Shimano Ultegra model and $6,000 when sold with the P5 Tree with SRAM Red model.
The custom handlebars are original equipment on 2013 Cervelo P-Series bicycles, which come in black, gray and red combinations, the Consumer Product Safety Commission said.
The handlebars have a gloss black finish with "3T," "AURA-PRO" and "ULTIMATE PERFORMANCE" in white letters on the top surface.
Consumers were advised to stop using the bicycles and obtain a free repair kit from 3T Design.
The repair kit includes four replacement bolts and instructions.
The bicycles can also be taken to a Cervelo dealership for a free repair.
Consumers can call 800-223-3207 for information.