Mecacycle Turbo Frame / 55 cm

Mecacycle Frame with chromed Fork
Legendary model Turbo, launched in 1980, with a split seat tube and extremely short wheelbase for very agile handling combined with increased rigidity.
pretty sure made of french Super Vitus 980 tubing in Fillet Braze 
Internal brake cable routing

In 1978 Raymond Crozet, who spent most of his career as a frame builder and designer for Mercier, set up his own business in the heart of the French bicycle industry in Saint-Étienne. He founded the company Mécacycle, one of the last French quality frame builders. He also worked for Vitus and Stronglight, among others, and designed the first French MTB in 1983.