obrentharris 

In the process of my Olmo project I have acquired 2.9 Gran Sport derailleurs. I also have a set of the steel pulleys from a Record derailleur. I have noticed that there are two different styles of pulley cones. Three of my pairs of cones have a slot on the male side and flats on the female side, but one pair has flats on both sides. More common style shown on the right in these two photos. Less common on the left.






For those of you who have not taken apart a Gran Sport pulley, they have ball bearings and cones. Here is a photo showing them in different states of assembly.



Was this a production change that took place at a known date? Which is earlier and which is later?
Or is the oddball from a Sport derailleur, or not Campagnolo at all, but some other manufacturer with a similar pulley?

...About that .9 Gran Sport mentioned above; Its cage stop screw is broken and one of the pulley bolts is incorrect.. Anyone have spares?

Brent

3speedslow

Which generation is your Gran Sport?

obrentharris 

All are with the black hanger bolt and pivot bolts. The one with the different pulleys does not have the cable adjuster, so last generation I assume. The ones with the slot and the flats are one with cable adjuster and one without.
Brent

obrentharris 

Perhaps Professor @juvela will happen along and provide a little illumination.
Brent

oneclick 

I posted this:

https://www.bikeforums.net/classic-v...-question.html

Additional info - either or both of the jockey wheels in my post might be from either a Gran Sport or a Sport; I have bits of both and can't remember which came from which.

Until I know I will use Huret Allvit wheels in a menage-a-trois:

https://www.bikeforums.net/classic-v...g-picture.html

And I may have a stop pin and/or pulley bolt, can you post pics of them for me to check?

obrentharris 

@oneclick thanks for your reply. I hadn't thought to check the thickness of the pulleys, so I checked this morning. All of mine are right around 10mm thick.
I really like your idea of mating the sprung top section of a Sport derailleur with the bottom section of a Gran Sport! I think I saw a mention of this marriage by Jim Merz over at Classic Rendezvous. Have you managed to make it work yet? What rivets do you use?
Here's a photo of examples of the two screws I seek.


Brent

obrentharris 

Here is a partial answer to my questions :
See the two little nubs cast into the cage plate right next to the holes for the pulley bolts? Those little nubs fit very nicely into the grooves in the grooved style pulley cones shown above, thus keeping it from moving when you adjust the cone with the flats on the opposite side of the pulley. If you don't align the pulley slots with the nubs your pulley will sit in the cage slightly skewed. I don't know why I didn't notice this before!



I examined three Gran Sport derailleurs, one with the cable housing adjuster, two without. All of them had those nubs. I also looked at two Record derailleurs, neither of which had the nubs.
I'm sure there are early versions of the Gran Sport that I have not examined, and I have yet to get my hands on any Sport derailleurs.

Does anyone know where to get a very thin cone wrench that would easily adjust the pulley cone with the flats?

Brent

bulgie 

Here's my Gran Sport pulley wrench:

It's a Craftsman "ignition wrench" from the '70s, that I ground down thinner on a belt-sander. A bench-grinder would work also. Looks like Craftsman doesn't make that set of ignition wrenches anymore (does Sears even exist anymore?) but there are other similar options. The advantage of starting with the ignition wrench is it's thin to begin with, less metal to take off.

Sharp-eyed readers will notice this mech is a hybrid, with the top knuckle from a Sport grafted onto the rest of a Gran Sport. The spring in the upper pivot vastly increases the range of gears it can work on. A couple more pictures here. I haven't put this one on a bike yet, but here's some pics & info about my Record-Sport hybrid, which I have put some miles on. That one is currently shifting a 14-30 freewheel with a 20-tooth difference in front. Can probably handle more; it's not maxed out. I expect the Sport-GS will be similar, maybe a tad less range.

Mark B in Seattle

obrentharris 

Thanks Mark!
Deep in the recesses of my tool box are some old Craftsman ignition wrenches. Hopefully there is one as large as 11mm.
Your hybrid derailleur has given me yet another reason to find a Sport derailleur.
Brent

John E

Cool! I like 11mm, because I can substitute a 7/16", if that is handy. I have a super cheap set of thin combo wrenches that includes a 7/16".

oneclick 

Sorry, I didn't see this until now. I'll have a look today for the screws. I made the rivets.

repechage

boy, that is a clean mechanism!