According to the Larousse dictionary, the name, "derny" has become a generic term for a small pacing motorcycle used in cycle races, and is now applied to all small cycle-pacing vehicles, regardless of manufacturer. There have been several attempts to copy or improve the original. One, the Burdin, was briefly used, but proved neither durable nor fast enough for repeated high-speed riding on the steep tracks used in six-day racing. Modern machines are made by a small company in Neerpelt, Belgium, and dernys are either new or have the original frames with new engines.