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cgolvin
03-25-2019, 11:00 AM
Revisiting a previous thread now that I've got everything assembled.
Background: replaced my standard NR crankset with a compact Veloce (concession to steep climbs on Eroica).
Freewheel is a 7 speed 13-28.
Chain is KMC 9-speed.
Looking for insight on both derailleurs. I've only tested it on the stand, will try to take it out for a shakedown ride later this week.

I finally put the chain on yesterday and did fine tuning on derailleurs. Using OP's trusty small-small chain length guidance, on my first try there was not enough clearance between the upper pulley and the 28, though all other combinations seemed good. Since I'm looking for low end that wasn't acceptable so I took out one more link. It's now good in the 34-28 but clearly too short for the 50-28…that's ok, wouldn't use that anyway but I need to remember not to.

The front will shift up to the 50 but only at the very end of the shifter's range and that shift is not very smooth. I suspect I will have to shift somewhat gingerly. The derailleur is mounted with the bare minimum of clearance for the big ring and in the 34-13 the chain rubs slightly along the back of the derailleur. Again, don't need that combo and it's a good reminder to just avoid both cross-chain combinations. My guess is that a 16 tooth gap is at the extreme end of what the NR FD is able to do so I should be happy that it works with these limitations.

Interested in any feedback, especially from anyone who has been able to make this configuration work better than I've described my setup. Thanks.

stien
03-25-2019, 11:21 AM
Here's an exhaustive thread on the classic and vintage forum about this very topic:

https://www.bikeforums.net/classic-vintage/315066-campagnolo-nuovo-record-rear-derailleur-problems-2.html

I love those guys.

I seemed to recall that there was no b-screw on the NR RD, you only have chain length, spacers behind freewheels, and horizontal dropouts to play with.

I would certainly account for being able to shift into the big-big without destroying things.

As for the front, you mention that it's at the end of the shifter range, is there enough cable slack to take some up so it shifts earlier in the lever range?

cgolvin
03-25-2019, 12:48 PM
Here's an exhaustive thread on the classic and vintage forum about this very topic

I seemed to recall that there was no b-screw on the NR RD, you only have chain length, spacers behind freewheels, and horizontal dropouts to play with.

Thanks; though with the exception of one comment on using a triple they all seem to be using a standard (52/42) crankset.
My wheel is already as far back into the dropouts as possible (should have mentioned that, sorry).

I would certainly account for being able to shift into the big-big without destroying things.

As for the front, you mention that it's at the end of the shifter range, is there enough cable slack to take some up so it shifts earlier in the lever range?

At this point, I'll trade off being able to use the 34-28 with remembering to avoid 50-28.

There's no slack in the front cable at all.

stien
03-25-2019, 01:25 PM
Roger that. Is there enough gap between the 13 and the dropout to try a spacer behind the cluster?

cgolvin
03-25-2019, 01:30 PM
Roger that. Is there enough gap between the 13 and the dropout to try a spacer behind the cluster?

Doubt it — I guess I could try to find a 6 speed with a 28, but given that Eroica is 13 days away I don't relish the thought of changing the freewheel.

stien
03-25-2019, 01:41 PM
You could always try throwing a washer on the RD mounting bolt.

David Benson
03-25-2019, 02:03 PM
Ive successfully run Nuovo Record deraillers with 47/34 TA cranks, and also Zeus 49/36.
Its easier with the long 1010 dropouts that allow you to slide the wheel back behind and away from the derailler.

50/34 with 13-28 is a few teeth more than the capacity of the derailler. Rather than risking disaster in the event you accidentally shift ino 50x28, I suggest letting the chain run slack in 34x13.

This is on the Masi with 49/36 rings that I rode at Eroica last year. Sorry for the extra-low fidelity.

https://farm1.staticflickr.com/796/41267443222_cc3ac7e43b_z.jpg

cgolvin
03-25-2019, 02:09 PM
Rather than risking disaster in the event you accidentally shift ino 50x28, I suggest letting the chain run slack in 34x13.

Thanks. But based on my first try, I think slack in 34x13 would bring the upper pulley back into contact with the cog in 34x28.

sg8357
03-25-2019, 04:46 PM
You need a vintage solution,

https://store.somafab.com/sonuredecapl.html

Long cage for the NR derailleur, note this gives you front ring range,
not big cogs in back. 13-25 in back 46/32 in front using a Stronglight 49a
and VeloOrange copy.

mtechnica
03-25-2019, 04:53 PM
I put an IRD defiant on my girlfriends super record equipped bike and have this exact problem. She likes the big ring so I have it set up to go loose in the small smalls, but I think it could be better - glad there’s some ideas in here.

David Benson
03-25-2019, 05:02 PM
Thanks. But based on my first try, I think slack in 34x13 would bring the upper pulley back into contact with the cog in 34x28.

Can you move the wheel back further in the dropout?
I understand that youve posted about this previously but it might help if you could reiterate what frame you have, and what dropouts.

cgolvin
03-25-2019, 05:13 PM
Can you move the wheel back further in the dropout?
I understand that youve posted about this previously but it might help if you could reiterate what frame you have, and what dropouts.

It's buried earlier in the thread, but the wheel is already as far back as it will go.

It's a 1978 Gios Super Record with Campy dropouts: https://forums.thepaceline.net/showthread.php?t=196689

stien
03-25-2019, 05:35 PM
I’ll reiterate the washer on the mounting bolt suggestion. If the upper pulley does indeed follow a non-straight path across the cogs towards the largest, it might buy you the clearance you need.

It also goes without saying that you oughta check your rd hanger with an alignment tool.

muz
03-25-2019, 05:48 PM
I think your easiest path is to use a different crankset, e.g. a vintage TA using smaller rings, like 40-28. You will not need a taller gear than 40/13 unless you are racing it; just tuck and coast.

choke
03-25-2019, 05:57 PM
I have one bike with a 35/48 Victory crank and a 13-28 rear with NR derailleurs. I can shift to every combo but it's pretty tight in the 48/28.

As for the front derailleur, another bike has a 30/46 TA crank and a 13-28 rear with a NR FD and a Rally RD. The FD shifts that 16 tooth difference just fine and obviously the extra length on the RD cage means there's no problem at the back.

I'd agree that probably the best solution is to put a Soma cage on the RD.

Spaghetti Legs
03-25-2019, 06:11 PM
At this point 2 weeks out I think you’re right to tune it to the small front, big cog performance. Jus twat h out for the cross chaining and after all, it’s a low key, mellow event, not a race so you won’t be losing track of what gear you’re in.

I have a VO 46-34 crank with Super Record RD, 13+26 freewheel. 10 speed Chorus chain. I tested it on a 28 tooth freewheel and got it working fine, but had problems with the freewheel unrelated to the setup. I’ll see you out there on my red Francesco Moser!

David Benson
03-25-2019, 06:11 PM
My only other suggestion is to try a second generation Super Record rear derailler or a Super Record pulley cage.
They are supposedly good for a couple of teeth more chain wrap, and possibly a bit more clearance between top pulley and big cog.

https://farm3.staticflickr.com/2608/3778713763_62ea08d606_z.jpg

cgolvin
03-25-2019, 06:42 PM
I see quite a few SR derailleurs on eBay but they're all a slightly later vintage, not the lovely metal body but black with 'Campagnolo' in script. Like this:

https://www.ebay.com/itm/VGC-Campagnolo-Super-Record-Rear-Derailleur-w-Sealed-Pulleys-Retro-LEroica/153427328848

I'm not sure whether these have the additional wrap of the very beautiful one above, and I'm even less sure about plunking down the funds for this experiment. So at this point my main concern is the FD shifting, will take her out for a spin and see what it actually feels like.

Thanks to everyone, I heart paceline.

David Benson
03-25-2019, 07:05 PM
I see quite a few SR derailleurs on eBay but they're all a slightly later vintage, not the lovely metal body but black with 'Campagnolo' in script. Like this:

https://www.ebay.com/itm/VGC-Campagnolo-Super-Record-Rear-Derailleur-w-Sealed-Pulleys-Retro-LEroica/153427328848

That is the one you need.
The one in my photo is a Nuovo Record derailler with Super Record cage.

rccardr
03-25-2019, 07:45 PM
A LOT depends on the length of your RD hanger. Generally speaking, a 50/34 and 13 or 14/28 combination should work well with an 8 speed chain and measuring chain length at Big/big plus 2 links. Axle should be all the way in back of the dropout.

If when set up that way the upper RD pulley contacts the freewheel in small/big, the onply thing I'be ever done that consistently works is to switch to a late 70's-early 80's SR RD. Or a Deore.

At Eroica you'll mostly be in the big ring unless you're in the two or three larger rear cogs, so small/small is irrelevant.

Tandem Rider
03-25-2019, 07:59 PM
The old trick back in the day was to remove the dropout adjuster screws. I've seen guys run a 32 with a NR rear derailleur by removing the adjusters. It's a cheap try it now solution.

zennmotion
03-26-2019, 04:21 PM
You need a vintage solution,

https://store.somafab.com/sonuredecapl.html

Long cage for the NR derailleur, note this gives you front ring range,
not big cogs in back. 13-25 in back 46/32 in front using a Stronglight 49a
and VeloOrange copy.

^^^ this is your solution if you want to use a vintage campy RD with a wider range or a triple. OR you can use a vintage Suntour or Shimano long cage derailleur that will arguably shift better :fight: BITD everybody got along just fine.
https://store.somafab.com/sonuredecapl.html

Mark McM
03-27-2019, 09:53 AM
^^^ this is your solution if you want to use a vintage campy RD with a wider range or a triple. OR you can use a vintage Suntour or Shimano long cage derailleur that will arguably shift better :fight: BITD everybody got along just fine.
https://store.somafab.com/sonuredecapl.html

Or, you can use a vintage Campagnolo derailleur that was actually intended to be used with large range freewheels, such as a Rally which is spec.-ed for a maximum sprocket size of 36 teeth:

http://velobase.com/CompImages/RDerailleur/9B081287-C0B4-4AEF-82B6-4E1753BCA9F0.jpeg