new rear derailer for a vintage 10 speed



Airfoil

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Sep 6, 2004
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I'm rebuilding a 30 year old Legnano road bike, (10 speed, friction shifting) and thinking of getting a newer, (probably used) "index" rear derailer. Of course, I don't expect it to index shift...but it should work, right? or am I assuming too much? I saw a used Campy long cage 8 speed on Ebay and thought I could replace the old campy NR short cage so I can put a larger freewheel on the bike.
 
Airfoil said:
I'm rebuilding a 30 year old Legnano road bike, (10 speed, friction shifting) and thinking of getting a newer, (probably used) "index" rear derailer. Of course, I don't expect it to index shift...but it should work, right? or am I assuming too much? I saw a used Campy long cage 8 speed on Ebay and thought I could replace the old campy NR short cage so I can put a larger freewheel on the bike.
An index RD will work.Don't assume a long cage with shift a bigger cog.Cage length is about chain wrap capacity. Large cog capacity is in the parallelogram. An MTB RD will shift big cogs.
 
boudreaux said:
An index RD will work.Don't assume a long cage with shift a bigger cog.Cage length is about chain wrap capacity. Large cog capacity is in the parallelogram. An MTB RD will shift big cogs.
I've got a feeling I'm about to open a can of worms here...

OK, I've got a 53/42 front and more or less a "corncob" freewheel on the back, with a Campy NR rear Derailer. (at 53, I can't pedal like I used to)
Is there somewhere, someone who can tell me the biggest freewheel that will fit with that set-up? I'm guessing a 22 or 24 cog would be about max...

A MTB RD is a option, but I would like to keep the bike "all campy" if possible...I've seen the new Campy road RD's come in long, med. and short cage, and assumed...(there I go, again) that would do the trick.

I understand that a few years back Campy made MTB components, as well as "touring" rears, both of which seem rather expensive now due to limited availability (I guess)...used "newer" Chorus and Record 8 speeds are going for less than a old Rally touring long cage...

I guess I might pay for a brand new Chorus... if I knew it would work... I really love the old Legnano..first real bike and all...still works after all those years.
 
boudreaux said:
An index RD will work.
Would it really? There was this this Shimano low-end road RD (positron?) years and years ago which had the indexing in the RD. There was a serrated comb stuck in the parallellogram that was supposed to line up to the cog spacing. Most easily recognised by the use of a solid piano wire instead of the usual multi-strand cable between shifter and RD. The ones I've seen were 6-speed and would require some serious remodelling to work on a 10-speed.
OTOH if you're talking about a RD from a normal indexing system, with the index in the shifter, then that would work.
 
dabac said:
Would it really? There was this this Shimano low-end road RD (positron?) years and years ago which had the indexing in the RD. There was a serrated comb stuck in the parallellogram that was supposed to line up to the cog spacing. Most easily recognised by the use of a solid piano wire instead of the usual multi-strand cable between shifter and RD. The ones I've seen were 6-speed and would require some serious remodelling to work on a 10-speed.
OTOH if you're talking about a RD from a normal indexing system, with the index in the shifter, then that would work.
And how many of the positrons? do you think are running around today? Were are taalking about reasonable current stuff here.
 
Airfoil said:
I've got a feeling I'm about to open a can of worms here...

OK, I've got a 53/42 front and more or less a "corncob" freewheel on the back, with a Campy NR rear Derailer. (at 53, I can't pedal like I used to)
Is there somewhere, someone who can tell me the biggest freewheel that will fit with that set-up? I'm guessing a 22 or 24 cog would be about max...

A MTB RD is a option, but I would like to keep the bike "all campy" if possible...I've seen the new Campy road RD's come in long, med. and short cage, and assumed...(there I go, again) that would do the trick.

I understand that a few years back Campy made MTB components, as well as "touring" rears, both of which seem rather expensive now due to limited availability (I guess)...used "newer" Chorus and Record 8 speeds are going for less than a old Rally touring long cage...

I guess I might pay for a brand new Chorus... if I knew it would work... I really love the old Legnano..first real bike and all...still works after all those years.
Any of Campy current '10 speed' medium cage will work in your application and will shift a 29 rear cog. Veloce or Centaur will work and you don't have to spring for chorus. An older 8/9 speed 'racing triple' and veloce long cages were were also speced for a 28 large cog. The short cage 8/9 speed types were speced for a 26 cog,and would probably handle a few more.
 
boudreaux said:
And how many of the positrons? do you think are running around today? Were are taalking about reasonable current stuff here.
Well, you're usually a stickler for accuracy - and suddenly you start talking about index RD , which sounds like it means a RD that does the indexing. The "reasonable current stuff" might be indexing systems, but not indexing RDs.
 
dabac said:
Well, you're usually a stickler for accuracy - and suddenly you start talking about index RD , which sounds like it means a RD that does the indexing. The "reasonable current stuff" might be indexing systems, but not indexing RDs.
It wasn't me that threw out the term 'index' RD in the first place... and the poster WAS referencing current stuff designed for post 1985 index shifting.