Just to add my 2 cents, I've been using Ti Duopars continuously since around 1980 with excellent results and always with Campy friction bar ends. My half step plus granny is extreme in the least at 28-53 in front and 13-32 in back. Yet the derailleur picks up and goes smoothly into gear with its required light touch. This is not a crunching derailleur. I have bent the ti version jockey cage a few times when the chain got stuck between chainrings, usually on an epic cross state ride near the bottom of a hill nowhere near any mechanic. Once I got the chain free, the cage was soft enough to bend it back by hand with some fine tuning later if necessary with a couple of adjustable wrenches (the older mechanics know what I'm talking about). I've never seen any other derailleur that shifts such a wide range with such aplomb. I have recently run into some problems with newer narrower freewheels that don't seem to index the derailleur as well. Building up a NOS half step Suntour freewheel got the perfection back. The big problem with this derailleur is finding a long enough front caged derailleur to match the extreme gearing in back. What worked and is still working for me is an old Mountech front that still allows four of the half step cogs in back when in the granny, a 28x17 gear and still gets the 53x32. Thats wrapping 40 teeth worth of chain.
I've just reinstalled my first generation rear Campy Ralley derailleur on a Raleigh Pro (an abomination, yeah I know), and maybe I'll get the bugs worked out soon, but the Campy record front doesn't presently do the alpine triple very well at all, not even counting the cage not being long enough. The ralley was ok, but never shifted as well as the Huret. I experimented with using a ralley jockey cage on a record rear with totally crappy results for a 13-28 freewheel. Much better was the Mavic record copy with adjustable short cage that handles a 28 tooth freewheel with aplomb.
Happy trails, and looking forward to the Cirque'
Dan Artley in Parkton, Maryland
>>> JohnThompson@new.rr.com 04/17/2005 10:48:42 PM >>>
I remember a SunTour "Mountech" derailleur matching what Leonard describes in the early 1980s, maybe as early as 1981. As he notes, it worked quite well until it got dirty, and them it became unusable. John (john@os2.dhs.org) Appleton WI USA