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-   -   Campy Nuovo Record RD question (https://www.bikeforums.net/classic-vintage/1163924-campy-nuovo-record-rd-question.html)

shoota 01-09-19 08:05 PM

Campy Nuovo Record RD question
 
I have a 1970 Campy NR rd that does not keep the chain tensioned. I'm not familiar with this component and almost seems like it is just gunked up. It did come off a poorly maintained bike so I suppose that's possible. If that's the case how do I best clean it out? If there's a spring in there somewhere could that be the problem?

https://i.postimg.cc/9QHLqRtg/nr.jpg

PilotFishBob 01-09-19 08:20 PM

There is a spring in the cage pivot, I've cleaned them out with mineral spirits then lubed again. Not hard to take apart - I've never seen one with a weak spring, that may be possible though. Here's a thread on that with an exploded diagram: https://www.bikeforums.net/bicycle-m...-question.html

76SLT 01-09-19 08:41 PM

I had one that I thought had a weak spring too but it was just very gunked up. Cleaned it thoroughly and all the tension returned. It's not difficult to do.

shoota 01-09-19 09:07 PM

Thanks guys! I searched for that but didn't see it, I'll give it a good cleaning and see if that helps.

SurferRosa 01-09-19 09:45 PM

Use a screwdriver and remove the grub screw/cage pin thing. Then unwind it and fully disassemble. When you reassemble, there will be two pin holes to choose for the cage spring. Try the one that provides the least resistance first, and test. :thumb:

shoota 01-09-19 10:09 PM


Originally Posted by SurferRosa (Post 20740596)
Use a screwdriver and remove the grub screw/cage pin thing. Then unwind it and fully disassemble. When you reassemble, there will be two pin holes to choose for the cage spring. Try the one that provides the least resistance first, and test. :thumb:

Ooo, I went with the hole with the most spring tension. But, I think there may be other things wrong. I'll report back later, time for bed. Thanks.

Chombi1 01-10-19 04:36 AM

You need to "preload" the cage with enough spring tension before you reinstall the cage stop post on the derailleur. That is done by twisting the cage assembly around on the lower pivot. You also have to make sure that you do not have a broken tension spring. You will know if it is broken if you cannot build up enough tension in the cage assembly by twisting it around.

Prowler 01-10-19 05:12 AM

I've just recently started the overhaul on my Patent 72 NR RD. I cannot see the photos in the mentioned thread due to the Photo Bucket business model. But I've had no troubles. I made a schetch of my RD prior to disassembly (or take a picture) to help with the spring tensions.

There are 2 locations with two holes - one in the cylinder that fits on the end of the spring housing and a second on the cage plate. You need to get both right. On my RD, for the two holes in the cylinder one leaves the threaded hole for the "grub screw/cage pin thing" exposed. The other rotates that hole in under the RD body. Mine had the hole exposed so I kept it that way.

Similar idea with the holes in the cage plate. One hole rotates the plate more clockwise (looking from the outside, with the parallelogram face up) the other rotates it more counterclockwise. I chose the later as that's the way it was originally.

I trust you pulled the tension spring completely out and cleaned EVERYTHING. My old grease looked like brownie dough, very thick and gooey. Obviously slowed the cage movement.

One other thought. OP, your photo in post #1 shows, at the upper center, the 'screw' that holds the parlellagram spring in place. The head of your screw looks not flush with the RD body, cocked a bit. Look carefully to see that the screw (actually a threaded stud with the spring held by the unthreaded end) is ok and goes straight in between the plates, holds the spring coiled end straight.

repechage 01-10-19 09:52 AM


Originally Posted by SurferRosa (Post 20740596)
Use a screwdriver and remove the grub screw/cage pin thing. Then unwind it and fully disassemble. When you reassemble, there will be two pin holes to choose for the cage spring. Try the one that provides the least resistance first, and test. :thumb:

Five star answer, be sure to use low viscosity grease.

shoota 01-10-19 03:28 PM


Originally Posted by Prowler (Post 20740859)
I've just recently started the overhaul on my Patent 72 NR RD. I cannot see the photos in the mentioned thread due to the Photo Bucket business model. But I've had no troubles. I made a schetch of my RD prior to disassembly (or take a picture) to help with the spring tensions.

There are 2 locations with two holes - one in the cylinder that fits on the end of the spring housing and a second on the cage plate. You need to get both right. On my RD, for the two holes in the cylinder one leaves the threaded hole for the "grub screw/cage pin thing" exposed. The other rotates that hole in under the RD body. Mine had the hole exposed so I kept it that way.

Similar idea with the holes in the cage plate. One hole rotates the plate more clockwise (looking from the outside, with the parallelogram face up) the other rotates it more counterclockwise. I chose the later as that's the way it was originally.

I trust you pulled the tension spring completely out and cleaned EVERYTHING. My old grease looked like brownie dough, very thick and gooey. Obviously slowed the cage movement.

One other thought. OP, your photo in post #1 shows, at the upper center, the 'screw' that holds the parlellagram spring in place. The head of your screw looks not flush with the RD body, cocked a bit. Look carefully to see that the screw (actually a threaded stud with the spring held by the unthreaded end) is ok and goes straight in between the plates, holds the spring coiled end straight.

Thanks for the answers everyone. Prowler, that's just a stock photo. I still have some to learn about this derailleur however I'm concerned it's broken.

Here's a pic of my rd, showing what looks like a screw/bolt and part of its housing broken off. I'm not sure what this screw/bolt is responsible for yet:

https://i.postimg.cc/fTYG4Kdf/IMG-1302.jpg

SurferRosa 01-10-19 03:51 PM

^ Never seen that kind of damage before. Looks like you need a replacement spring cage cover and grub screw.

http://www.os2.dhs.org/~john/campy-der.jpg

Chombi1 01-10-19 03:55 PM

That looks like where the jockey wheel cage stop screw (Part 812/1A) goes into.
The RD should still work, but it could present a hassle when removing the rear wheel as the jockey wheel cage assembly will keep trying to twist the chain as you try to get the wheel away from the bike...

SurferRosa 01-10-19 04:19 PM


Originally Posted by shoota (Post 20741756)
I'm not sure what this screw/bolt is responsible for yet:

It's pretty obvious your cage tension spring wasn't loaded properly to tension the chain. It's probably difficult to do if the grub screw is missing. the grub grub screw allows you to load the spring and then prevents it unwinding all the way when the chain doesn't hold the tension (like when the derailleur or wheel isn't mounted.) In the video, notice the grub screw stops the cage from unwinding after he pulls and releases the cage by hand.


Youtube hack, rj the bike guy, has a couple suntour derailleur videos where he shows how the grub screw is removed before unwinding the cage and then replaced after he overhauls the derailleur. Search youtube for "suntour overhaul."

Drillium Dude 01-10-19 05:52 PM

I wonder how common this is? I had it happen to me with an NR bitd, but never since. Others have shown similar damage in recent years here.

In any case, this is your problem and as others have suggested, the problem will be solved with a new collar and grub screw.

Might keep your eye out for a beat-to-death one and buy it for spares. I'd assist, but I'm down to only one collar/screw spare and as I'm seeing lately, one day this might happen again to me so I'd better stay prepared!

DD

shoota 01-10-19 08:49 PM

OOOOH I see what it is and why it's broken off the way it is. So I figured out why the rd felt so slack, it wasn't "wound" all the way around, because the grub screw is broken off and the cage is allowed to go way too far around. Thanks guys.

Prowler 01-11-19 05:55 AM

As this is a 'light duty' application, I wonder if you can rig a stud so you can ride it while searching for the correct parts. Find the correct metric screw (3 or 4 mm?) as long as the proper grub screw. Screw it into place and cut to length. Maybe reinforce at the cover broken section with a zip tie. In normal use this grub screw is not in play. Only when you fully slack the chain during wheel removal or RD removal. Just take it real easy when you do this to prevent tiny damage to the RD lower body. You could even cover the exposed threads with plastic tubing or heat shrink.

Maybe you could run the temp screw in from the back side so you don't have to cut the head off. I've not looked to see if that cover is threaded right through. I'll bet it though - easier to manufacture.

jimmuller 01-11-19 06:04 AM

What they said. You really don't need the grub screw. It is a convenience for when you remove the wheel. If you find an inexpensive broken NR RD to use for parts, then replace that section. But until then just reassemble and ride while you are looking for one.

Prowler 01-11-19 11:51 AM


Originally Posted by Prowler (Post 20742516)
Maybe you could run the temp screw in from the back side so you don't have to cut the head off. I've not looked to see if that cover is threaded right through. I'll bet it though - easier to manufacture.

Bad idea. You could run a temp screw in from the cage end of the cover but the head of the screw would interfere with the cage as it swung around. Scratch this one.

Kactus 01-11-19 04:01 PM

I checked my parts bin and I have a spare I could send you. Just send me a pm with your address.

shoota 01-12-19 05:45 PM


Originally Posted by Kactus (Post 20743408)
I checked my parts bin and I have a spare I could send you. Just send me a pm with your address.

Thanks! What goes around comes around I suppose. I just helped a friend complete his Campy seat post that was missing the bottom rail cradle with the one from my cracked seat post. And now I can complete my RD. Score!


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