Fred Rednor wrote:
>
> Doesn't it make you wonder why Campagnolo didn't just remove
> the outer most 1 or 2mm from the spider section of all the
> 144mm BCD cranks? After all, it looks to me as though the
> "lip" that supports the chainrings is at the same diameter for
> both the 144 and 151mm cranks; i.e. they're the same forging.
> For 144mm they seem to have simply moved the bolts as far
> inwards as possible (about 2mm?) without having them interfere
> with the mounting lip. If so, why not remove the excess
> material from the top edge?
Simple explanation actually. The 144mm crank was intro'd in 1966. I wasn't aware of a 41 tooth chainring being available until 1984 (saw my first one on Jonathan Boyer's bike he rode in the TdF that year). The chain links hitting the end of the crank spiders when using a 41 tooth ring is not actually a problem as the chain links very quickly wear a small divot in the ends of each spider... at least that has been my experience with the 41 tooth Campagnolo ring on my Confente.
Chuck Schmidt
South Pasadena, Southern California
United States of America
http://www.velo-retro.com (reprints, t-shirts & timelines)