# Campy NR rear derailleur gear capacity



## imroadman (Mar 22, 2007)

Think I goofed...

Have an '84 Trek 660 w Nuovo Record drivetrain (but Maillard cassette). I'm mostly a mountain biker these days but have started taking my well-preserved road bike out more since I moved to a good area for both bikes, recently. 

The Trek has 13-24 - 42/52 gearing for 30yr old legs, not those of a 50-something. I bought a vintage 27 tooth cog online and installed it on the six-speed cluster, removing a 21 tooth cog to make room. Goal was to get some hill-climbing help, obviously.

Upshot is the bigger cog hits the upper jockey wheel, and, unlike my mountain bike, there's no adjusting screw. Think I could prob create a mechanical solution to rotate the mech slightly - out of the way - but it occurs to me that this race style mech was not designed for anything bigger than 24 tooth cogs. Will it shift thru the range ok if I move its stop over a little? Have one of those race weekend "fun" road rides coming up this weekend and I'll put things back to original if I have to...and grind it out...ugghh.


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## bobj (Sep 29, 2004)

I think the Nuovo Record could handle a 26t. You might need to play with the chain length though...


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## caterham (Nov 7, 2005)

the maxium tooth count for Nuovo Record and N Gran Sport was 24T, SR could wrap a 26T freewheel


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## imroadman (Mar 22, 2007)

Yeah...found out the bonehead way the 27 won't work. Installed it and it hits the top jockey wheel. Changing the stop on the dropout only rotates the cage in circle around the gear. Pulled it back off. I should have known...stupid.

Would've been some big gear-inch jumps in that 6-cog cluster anyway - something like a 25% decrease from the 21 to the 27.


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## caterham (Nov 7, 2005)

Since we must be around the same age , I definately wouldn't call that a "bonehead mistake", just a positive sign of your *optimistic* nature  

Myself,in a similar knee-saving act of "period-correct" desperation recently located a 41T Gipiemme chainring. Not much help I admit and more than I wanted to spend....but every bit counts at my age. Ofmega and Avocet also produced 41T inner rings to fit the Campy 144 bolt circle.









Another more effective option might be to hunt down the Campagnolo Rally cages which would convert your NR into a pseudo- "Rally" derailleur with an easy 28T capacity.Unfortunately, they're commanding hideous prices these days, if you can locate them at all.
There's a possibility that Victory/980 etc.long cages might be compatible/interchangable but I haven't personally tried any of those on a NR.

Then there's always just breaking down and ditching the NR for a 980/Victory long cage derailleur.Those haven't yet gone thru the roof on the used market and afford equal or better shifting performance to the NR/Rally. And of course, a SR might end up being your simplest and easiest to obtain solution and settle for a 26T cog.


Good luck and keep those knees warm.

best,
k


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## refund!? (Oct 16, 2006)

As has been stated, the Nuovo Record rear derailleur was limited to 26 teeth, but even that was a stretch - up to 25 teeth shifted pretty good. But you can switch to a Super Record rear derailleur - it will easily handle a 28 tooth cog (In fact that's what I'm running - Campy Super Record derailleurs with a 14-28 6-speed Regina CX-S freewheel and 42-52 rings).


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## Mapei (Feb 3, 2004)

My Nuovo Record derailleur, circa 1972 and still in regular use, currently swings a 14-26 cluster with 42-52 chainrings. It takes a crisp, solid throw along with a decrease in pedal force to get into the 26 and I never, NEVER go into the 26 when I'm in the big ring; but it generally works just fine. If you can find a 26 to spin onto the core, you'll be in business.


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## imroadman (Mar 22, 2007)

Thanks for the input, guys. Believe I will look for a longer cage derailluer. Anything reliable will do. Calculated I get more bang for the buck from a bigger cog than from, say, a 40 tooth chainring IF I could find one.

I'm 54... Rode that 36 mile organized ride this morning and there were a TON of hills in the first 10 miles. I stayed up with some strong riders in my 42/24 - breathin hard, but keepin the revs up. 

Got a lot of comments like, "How old IS that Trek?" and "Whoa, there's a classic transmission!" Gave them a chance to count my gears as I was passing them, hehe. You also I attract attention dropping the arm down to shift...


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## Spirito (Nov 26, 2001)

depends on the bike .... I've ridden NR with a 42/52 and 14/28 setup (raleigh international). long stays with the rear wheel set at the rearmost end of the dropouts is a key but overall the trick is running a chain only as long as you need and no more. a 42-28 should be easy to run as you should never use a 52-28 so don't even set up a chain length with that combo in mind. even the next gear down (52-25 or 24) is kind of an overlap gear and not needed. shorten that chain. Might sound a little silly but hike the wheel as far back as you can and shorten the chain more than you normally would do. there of course are variances with each bike, clearances etc. at worst you should be able to use a 14/26 no probs. wth most bikes you'll acheive this by removing the dropout adjustor screws and by moving the wheel back to the end of the dropouts you are in effect shortening the chain and fixing the issue at the same time. 

if you've tried with different length chains and wheel positioning and it doesn't work I'd not think twice about adding a suntour $20 V-Gt in place of the Nuovo Record and ride happy and content and geared as is practical. Italian race parts is nice but even the pro's in the day would have used whatever worked with a 42-30+ combo rather than what looked good or had collector cache or approval.


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## caterham (Nov 7, 2005)

I also highly recommend the Suntour GT's & medium cage derailleurs( ex: V,Vx,Cyclone,Superbe,AR,etc) as excellent, reliable and often cheap solutions that have shifting performance bettering the Campagnolos when used on wide range gearing. 

I still stand by the max cog recommendation of 24T for NR and 26T for SR however.

Sure you can shoehorn in more capacity by forcing the upper pulley out of it's intended operating geometry with high chain tensioning and sometimes you just get lucky in certain installations with longer than normal hangers or by changing the wheel location in the dropouts,etc. 
The "make-fits" mentioned only address the pulley to cog clearance.
They don't change the fact that the Campy short cages can only swing a given number of chain links.
Pushing the maximum capacity of the derailleur carries compromises that may or may not be acceptable, depending on the rider's tolerance/sense of humour over such things and the specific application 
(ex: the occassional dropped shift, the inability to use certain chainring/sprocket combinations, clunky/hesistant shifting that requires timed pedal force modulations to overcome, the altering of the bikes F-R weight distribution,etc.).

best,
k

curious-
re:"...up to 25 teeth shifted pretty good"...

what company made a 25T freewheel? I missed that one.


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