This is the name of a small lightweight cycle company based in St Etienne, the home of the French cycle industry. The company was in business in the 1980s..and had its ups-and-downs. Some of the framebuilders used to work in the Service de Course workshop at Mercier...just around the corner.
The company made all types of frames including training, track, time-trialling, touring, and cyclo-cross. The split seat tube model - the TURBO - is the company's best-known model, with this short-wheelbase design being available for road, track and cyclo-cross use.
The early frames were entirely lugless, but later ones had the investment cast bottom-bracket. Normally the frames were built in Super Vitus 971 tubing..but there was a choice of other tubes.
For some detail pictures and more information check the MECACYCLE section on
www.flickr.com/photos/cyclecrank/ . There's a lot of other interesting stuff on the site including some frames that I built under the BESPOKE brand-name.
Happy viewing
Norris