After trying to redefine road racing equipment with their Dura-Ace AX groupset, Shimano decided to redefine road touring, and brought out the Deore groupset, complete with a chainset that was an avant-garde interpretation of a TA Cyclotouriste, pedals that were modernist versions of Lyotard platforms and you name it. I loved it.
The rear derailleur, however, was a classic beauty, a 600 EX re-engineered with beefier knuckles, better protection of the spring in the front knuckle and Shimano’s new Centeron mechanism that ‘managed’ the overshift on changing.
Shimano struck lucky, as the Deore derailleurs accidentally proved to be ideal for the new mountain bikes that were suddenly the flavour of the moment. Even the Centeron mechanism seemed purpose designed for the long cable runs and unfamiliar feel of thumb-shifters.
Capturing the zeitgeist, Shimano packaged the later Deores in a box with the famous ‘Deer Head’ logo - and so this derailleur came to be known as the Deore Deer Head. Note, however, that the instructions mention neither mountain biking nor decapitated ruminant mammals - they unequivocally describe the Deore as ‘perfect for touring’.
This example is the more unusual mid-cage version - presumably it is ‘perfect for audax’ or perhaps a ‘perfect paper weight’.
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