Here is the catalog of Shimano Dura-ace (DA) and 600 AX. AX was series which concentrated to aerodynamics, and caused sensation in the world market. Back in those days, a number of bicycles which were equipped with AX full set appeared in world bicycle shows. I could feel enthusiasm of Shimano and profound interest of bicycle industries to this series.

Unfortunately, AX series was a great failure. It had gotten unfavorable criticism such as vulnerable DD pedal, uncertain movement of the brakes which had difficulty of maintenance, and poor aerodynamic effect and the like. AX disappeared from the market two years later after all.

However, its mechanism had several technologies which were inherited by present parts including Shimano group-set.

This catalog was offered by Mr. K. S.

These are the front cover and back cover.

Shimano had prepared huge wind tunnel for the development of AX series, struggled with aerodynamics earnestly. I was surprised because of Shimano's enthusiasm which challenged to suppress air resistance for group-set. However, I also wondered about the air resistance of a rider, and condition during the pedaling.

The catalog explained about the function of each part. W-cut mechanism, Super shift gear, and cassette type freewheel were designed for improvement of gear change performance as a group-set. DD pedal was produced from a viewpoint which considered how to use human power effectively.

The catalog explained about the improvement of gear change performance and brake performance. Index system and aerodynamic brake lever which are familiar nowadays appeared with the explanation.

The catalog declared 21.7% air resistance reduction proudly. However, I was wondering how it could have meaning, due to the data without a rider and movement. Next to the declaration, catalog introduced Dura-ace AX and 600 AX through 2 pages. I could feel Shimano's enthusiasm for the aerodynamics.

I understand that Shimano wanted to make an innovation seriously. The series ended in failure. However, experience and effort of the development for this series was used for successor group-sets, had established present Shimano. However, I have been feeling that bicycle market had lost its balance due to the strong presence of Shimano.