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PostPosted: Thu Feb 17, 2011 10:20 am 
Dirt Disciple

Joined: Thu Aug 19, 2010 11:38 am
Posts: 36
Location: Somewhere near a beach or a mountain
Any suggestions for how to gear a 6-speed 1980s Colnago for the Alps?

The rear is 126mm spaced, and we want to keep the original hubs/wheels. The bike's currently fitted with a triple, but it looks hideous and still doesn't give a low enough gear.

Planning to change the chainset and rear block, ideally to something Campag, and would like to get a gearing that approximates the lower-to-middle range of a modern compact. Not bothered about having bigger gears, as will be coasting downhill enjoying the view and recovering...

All suggestions welcome!


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PostPosted: Thu Feb 17, 2011 10:39 am 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
Posts: 2098
Location: Sheffield, top city
campag changed mid 80's to the modern chainring pattern. Prior to this a 41 chainring was the smallest, but 42 was standard fare. For the latest pattern a 39 smallest for a double, but I do recall seeing campag triple around '88.
At the back, to get a standard mech to work youre probably talking 28 max.

So if you want a double, realistically its 42-28 or 39-28


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PostPosted: Thu Feb 17, 2011 11:30 am 
Dirt Disciple

Joined: Thu Aug 19, 2010 11:38 am
Posts: 36
Location: Somewhere near a beach or a mountain
[groan]

That's not going to do it! Used to riding a modern 34/25, or even 27, in the Alps...

Maybe the Campag triple with a 28 is the way to go.

Thanks for the advice, though!


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PostPosted: Thu Feb 17, 2011 12:06 pm 
King of the Skip Monkeys
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Joined: Wed Nov 07, 2007 4:34 pm
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Location: Moomin Valley
Ask Ededwards, he's our man in the Alps


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PostPosted: Thu Feb 17, 2011 12:22 pm 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
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Location: Sheffield, top city
if you want to keep it period, but not necessarily campag, there are of course TA and stronglight chainsets and shimano MTB was around late 80's that would let you gear lower


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PostPosted: Thu Feb 17, 2011 1:24 pm 
Dirt Disciple
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Joined: Wed Oct 21, 2009 1:51 pm
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Location: Kingston
Mid 80s Campag Victory and Triomphe had 116 bcd cranks. They were available in 'leisure' versions which had 50:36 at the front and could take bigger sprockets at the back.

Have a look at the 1986 Victory / Triomphe catalogue.

The chainrings are probably hard to get hold of, but the leisure mechs come up on ebay quite often.


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PostPosted: Thu Feb 17, 2011 1:25 pm 
Dirt Disciple

Joined: Thu Aug 19, 2010 11:38 am
Posts: 36
Location: Somewhere near a beach or a mountain
Sounds perfect! Thanks for the tip.

Now I just have to find one...


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PostPosted: Thu Feb 17, 2011 1:27 pm 
Retro Guru
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Joined: Wed Dec 19, 2007 10:05 am
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Location: Brussels
As I just saw cromoman said, the Triomphe and Victory cranksets from the mid 80's both used a 116mm PCD and according to Velobase, "The 116mm BCD chainrings were listed in the catalogs as available with 35, 36, 37, 38, 39, 40, 41, 42, 43, 50, 51, 52 and 53 teeth". So, you could in principle have a 'modern compact gearing' on an old-ish Campag crank. Good luck finding anything other than 42T or 52T rings though!

My race bike in the 80's had a full Victory gruppo with Simplex retrofriction levers and Shimano 105 brakes. It rode pretty well like that, and just about indexed ok in the early 90's when I bodged a set of Synchro levers on. I failed completely to get the Victory rear mech to work with Ergoshifters though and had to ditch it for a comtemporary Athena one. No idea where the Victory mech ended up, I thionk I gave it away.

There was also a Victory triple but I've never seen one.


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PostPosted: Thu Feb 17, 2011 2:07 pm 
Old School Grand Master
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Joined: Wed Jul 25, 2007 2:04 pm
Posts: 3364
Location: Completely in the dark, thanks to me good mate Terry....
116mm BCD NOS Campag 36T ring currently doing the rounds on eBay from a seller in the US;

http://cgi.ebay.co.uk/116-BCD-NIB-Campa ... 45f8c4a003

Also worth contacting Helmut Berns at Sonic (http://www.soniccycles.co.uk/) as he may be able to source some new Gebhardt ones for you.

David


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PostPosted: Thu Feb 17, 2011 2:18 pm 
Retro Guru
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Joined: Mon Mar 02, 2009 4:22 pm
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What gearing have you got at the back? Maybe you need a wider spaced cassette?

(or if you're keepin' it real you need a wider spaced freewheel)

Some of the cassettes with the really big gears (like bigger than 28 teeth) just need a derailleur with a longer reach to clear it. I've also seen some rear cassettes with a much bigger 'granny gear' up at the top.


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