At 2:04 PM -0800 11/14/09, Peter Brueggeman wrote:
>Simon Bird opined "The thing I find interesting is that front
>clanger, rod or suicide derailleurs stayed in use on racing bikes
>for so long. Why was that? Surely their weight was greater and the
>cost of the Simplex and Huret gears wasn't so great...."
It was the other way around. First came cable-operated front derailleurs, like the Rosa. One problem with wide-range chainring setups (as used by cyclotourists) is that you can throw the chain off the rings when shifting to the small ring. Rod-operated derailleurs were seen as an advance, because they offered better control of the shifting. And they were lighter, of course - no cables, no shift lever, just a simple aluminum rod.
Racers probably followed cyclotouring practice when they first started using front derailleurs. The rod-operated front derailleurs worked quite well for the small gaps between chainrings used by racers, so why change them?
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