If the derailleur is almost but not quite breaking from shifting onto the large/large combo it's generally perfect.
Kurt Sperry Bellingham, Washington USA
2008/12/17 Greg Thies <gthies1@cox.net>:
> According to Barnett's Manual (Vol. 4, page 26-6), the perfect chain length
> can be determined by placing the chain on the outermost positions of front
> and rear rings and adjusting the chain length so that a line through the
> center of the two rear derailleur jockey wheels is perpendicular to the
> ground as the bike is sitting level. A tool I made for holding the chain in
> place while making these adjustments is a six inch piece of coat hangar bent
> at each end so it can be inserted into the links. This allows you to try out
> various chain lengths before you remove any links.
>
> Greg Thies
> Vienna, Virginia
>
> ****************************************************************************
> ****
>
> Date: Wed, 17 Dec 2008 11:28:17 -0500
> From: Jesse Hearndon <viper7990@hotmail.com>
> To: c r <classicrendezvous@bikelist.org>
> Subject: [CR]Chain length on 58 cm Ciocc?
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>
> What would the reccomended chain length in links be on an 86' Ciocc? I'm at
> 112 links now I think.
>
> Drivetrain
>
> 52-39 double
> 27-11 9-speed
> Dura-Ace chain
>
> Jesse Hearndon
> West Melbourne, FL