Introduced in 1987 (first appearing in August 1986 Catalog for the 1987 Year) Shimano 105 would introduce alot of new technologies that year. that would not be seen on Shimano 600 for another year. Technologies such as SLR (Shimano Linear Response) Brake systems in 1989 The grouppo was updated for 7 speed and it was replaced by the 105SC group in 1990.
The freehub body is uniglide but can easily be swapped out for a hyperglide unit if desired.
640g
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