Bicycle chain and motion transmission system comprising such a chain

A bicycle chain comprising an alternate succession of outer links and inner link connected to each other at respective end portions thereof, each outer link and inner link comprising two plates arranged parallel to and spaced apart from one another to define a housing space for a tooth of a sprocket or toothed wheel, wherein:

• each plate of each outer link has, at a central portion thereof, a first thickness;
• each plate of each inner link has, at a central portion thereof, a second thickness;
• each plate of each outer link and inner link has, at said respective end portions, a third thickness;
• wherein said third thickness is less than a sum of said first thickness and said second thickness;
• wherein each plate of each inner link has, at an end portion thereof, a thickness smaller than that at a central portion thereof.