I was able to make the Nuovo Record/Rally cage combo work on a Shimano Mega Range freewheel with a 34 tooth large cog. Even though the jump from the 24 to the 34 is pretty large and the combo rated at a 32 max cog I can make it shift through all the gears (with the small front chain ring of 42) with reasonable smoothness.
First I installed a 28 rear sprocket freewheel and that shifted perfectly. I put the 34 cog freewheel on and using the same amount of chain it would not climb up on the cog. The top of the derailleur cage was hitting the 34 cog. I took four links out and it shifted fine because it pulled the derailleur cage away from the cog, however when in the big chain ring and the 34 the derailleur was pulled too tight and I was afraid of problems even though I would not use that combo. I then added two links back in and it was perfect on the small front ring and runs through the gears very well. It will shift up to the 34 using the front large chain ring (52) but it is not happy about it. I doubt I will ever engage it that way.
I also have a Record RD that supposedly has a larger capacity than the Nuovo record and the Rally cage will fit but I really like the look of the Nuovo Record with molded letters over the Record with the printed letters. I may replace the tension spring and move to the tightest spring hole to give it a little more snappy shifting.
So, this combo (52x42 front, 14x34 rear) will work if the chain length is just right. There seems to be very little if any lattitude. I suppose drop out depth could be use to fine tune the "effective" chain length as well.
update: I moved the wheel forward just a bit in the dropout and it brought the jockey wheel a bit closer to the cog and made the shift a bit smoother without hitting the cage on the cog.
Last edited by RISKDR1; 07-18-14 at 08:06 AM.
I tried a Rally cage on a Nuovo Record RD and I didn't like the way it shifted. I ended up switching to a Rally with a Rally cage.
You can buy reproduction Rally cages now. Soma is one source.
If you want good shifting over a wide range, you need a derailer with a slant parallelogram. That means either a vintage Suntour or something made after their patent expired. The only exception I can think of is a Huret Duopar.
You'll be happy with yours if you don't mind over shifting and readjusting every time. They say it becomes automatic after a while. I never got used to it. The NR shifts that way even with the stock cage.
I must be more tolerant than you. I found the stock NR/rally cage shifted fine on the 7 speed Shimano with Shimano chain on the 13-28. It was not fast but did not have an over shift issue most of the time. I have only tested the 14-34 on the stand so I will see how it works on the road soon. I am now just a casual recreational 69 year old rider so super perfect shifting is not a big issue. What I don't like is skipping but I don't think that is going to be a problem.