Nuovo Record

Hi there,

Seeking your advice and experiences on the following:

I have bought a 1974 NOS Campagnolo Record high-flange hub on ebay Italy. It has no grooves that would indicate an English thread and it came from Italy, so I assumed naturally that the thread was Italian.

I laced it up. Then, I tried to mount my 1983 Campagnolo freewheel which has an Italian thread and works fine on other Campagnolo Record hubs with an Italian thread. I greased both hub and freewheel first.

The freewheel doesnīt screw on very easily and it doesnīt go in all the way to the hub shell. I can slowly make the moves easier by moving the freewheel back and forth with the help of the original Campagnolo freewheel tool but I feel that something is not quite right there.

Have I bought a hub with a French thread? I donīt have the right calipers etc. to check this and I canīt procure them now. I have no other freewheels at hand now. Can you please help me figure this out anyway?

Have you tried to mount an Italian threaded freewheel on a French threaded hub? What happened?

Have you used (ridden) such a combination? What happened? Note: I am light and I ride only leisurely.

Please donīt waste your energy on posting different thread sizes etc., I have all this information, thank you. I would be very grateful for your own experiences. Will I be able to use this (French?) hub and (Italian) freewheel after forcing the freewheel on the hub (I am almost done with that anyway)?

Thank you so much in advance!

Nuovo

juvela

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an Italian threaded gear block on a metric/"French" threaded hub is what is termed a "class c" fit - i.e. the parts with go together but damage/failure will ensue


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scarlson 

If you have a standard M6x1.0 bolt, and another American #10-24 screw, you can use these to measure the thread pitch on the hub. Put the screws against the hub threads, so they "mesh". Then you'll know if it's French or not. Campagnolo didn't put a groove in Italian or French threaded hubs, so it could be either.

I have put an English threaded freewheel on a French threaded hub. I rode it, rather hard, once, and everything stayed together. A track racer friend also used it as a loaner bike while she was in town for a wedding. I sold it to another friend, who I knew would not ride hard. She never rode it and it was stolen. I hate to think what would happen if I tried to take it apart! The hub I ruined was just an old Maillard with grumbly bearings and lots of corrosion. A Campagnolo hub is too nice to ruin this way.

repechage

French is different.
long ago, when French freewheels were already in short supply, guys would work an English freewheel on. Knowing that was all that should go on after.

italian on French was a No Go- the teeth profile between Italian and English is the big culprit in my book.

the diameters vary a bit too
sheldonbrown used to have the full explainer

Trakhak

My first tubular-tire-equipped racing bike was a Helyett track bike with all French parts. I stripped the rear hub by installing a BSA-threaded sprocket. The elderly mechanic in the local bike shop wrapped the hub threads with aluminum foil and reinstalled the new sprocket, which held for as long I owned the bike.

Nuovo Record

Thank you to everybody for your quick responses. Much appreciated!

I will try comparing this hub thread to another Campagnolo hub which is definitely Italian, with the help of the sunlight and a magnifying glass.

Since I am trying to match a used freewheel and a new hub, can it be that the hub thread has to be "broken in"? Would that explain my difficulties? As I wrote, the "Italian" freewheel works on other "Italian" hubs but these are used. Maybe I just happened to buy a hub with an imprecisely cut thread? Any chance in that, what do you think?

repechage

before stamping the thread type on hub shells Campagnolo used a code-

on the hub just beyond the threads and between the shoulder and the hub spoke flange was a code:

no groove- Italian
one small, thin groove - English
two small thin grooves - French. (but for a short while these did not receive them...)

With a good digital caliper you should get very close if you did not want to believe the decoder "rings"
Later hubs received stamped threading type instead of the grooves.

repechage

the page with the Sheldon chart

https://www.sheldonbrown.com/freewheels.html

Nuovo Record

I was aware of (and have seen) the "English" hubs with the one groove. I was not aware of the "French" ones with two grooves.

Does that "short while" you mention happen to include 1974, do you know?
Thanks!

repechage

My 1972 axle cone date hubs with French threads have two grooves.
I don't know after that. the best is to measure OD of the threads and use a thread gauge.

Nuovo Record

Sheldon Brown mentions that you can use a bottom-bracket cup to determine the thread of a freewheel:

"You may check the thread pitch of a freewheel by threading an ISO left bottom-bracket cup into it (not a right cup, which is left-threaded). The cup will go in easily if the thread pitch is the same"
(Not sure why he mentions an ISO cup)

==> Does this mean that I can try to screw the hub into the left side of the bottom-bracket shell of an Italian threaded frame to find out if it has an Italian thread?
This never even crossed my mind. Has anyone ever tried it?

repechage

I really think time to buy some tools.

Nuovo Record

Well, thanks for the advice (which I know is well-meant and perfectly reasonable) but I started this thread because this is currently not an option. As I wrote in my first post: "I donīt have the right calipers etc. to check this and I canīt procure them now."

Thanks for your time!

oneclick 

No.

Italian BB is 36mm.
Italian FW is 35mm

With side-to-side comparison all 24tpi threads will match, without an optical comparator or a very good eye and a loupe you can't tell if it's a mismatch on thread profile.
Side-to-side a 35x1 thread will mismatch noticeably over about 12 threads. You may not have quite that many on a hub.

I like a short bit of english-threaded steerer as a tester on a finger, if it's a mismatch it will rock back and forth slightly, if they match the threads will lock and you can feel when they do, no need to look.

oneclick 

I'm pretty sure the emphasis was on LEFT not so much ISO, but even given the nominal outer dimensional differences between ISO and (what he calls) British, which implies that ISO is bigger and would not go in an British freewheel, manufacturing tolerances are such that it almost always will.

However, a RIGHT side ISO cup won't go in any freewheel at all.

JohnDThompson 

Campagnolo did not put grooves on either French or Italian thread hubs; they assumed you'd be able to distinguish them when a mismatch didn't engage properly. Ofmega put two grooves on French thread hubs. An English thread bottom bracket lockring (1.37" x 24tpi) will thread onto an English or Italian thread hub, but will jam on a French thread hub.

JohnDThompson 

No, he means that you can thread an ISO/English (1.37" x 24tpi) bottom bracket adjustable cup into an English or Italian thread freewheel body.

Alternatively, you can thread an ISO/English bottom bracket lockring onto an English or Italian thread hub.

dddd

I'm almost willing to bet that an English-thread BB lock ring will nearly spin onto a French-threaded hub. The French hub diameter is smaller and the short length of threads on the lockring may not be enough to create noticeable interference.

I'm running a Uniglide freewheel on a French-threaded Tipo hub with no problems to report from riding in the foothills with standard gearing, 42x28 low gear. That said, I am a lighter rider.

scarlson 

You are right, I have done this on even the nicest French hubs (Maxicar) with a nice lockring (Campag) and it screws on easily.

repechage

some French threaded Campagnolo hubs did indeed have no identification. Makes things a bother. Some did.
my 1972 Bertin C-37 has two grooves and a Milremo ( Atom ) French threaded freewheel.

Trakhak

As I noted above, over 55 years ago, I ruined a French-threaded track hub by installing a BSA-threaded track sprocket, corroborating Sheldon Brown's observation from the page linked to above:

French freewheel may start to thread onto an ISO/British/Italian hub but will soon bind. An ISO/British/Italian freewheel will skim the top of the threads of a French hub and will slip forward if an attempt is made to use it. Do not force a freewheel -- you will ruin the hub.

Nuovo Record

Thank you for the replies so far. Looks like my NOS 1974 groove-less Campagnolo Record hub from Italy is a bit on the French side.

Maybe I still have a chance to explain the poor fit with "manufacturing tolerances", i. e. an imperfectly cut thread on the hub.

Has anyone ever had difficulties screwing a used Italian-threaded freewheel on a NOS Italian-threaded hub, even if both were greased?
Did you have to "break in" the hub thread before it worked smoothly?
(I had to do this with my factory-new motorcycle in 1994)

Nuovo Record

I have reached a conclusion. I will post how I got there because I think someone might have the same problem in the future.

I know now three (there are probably more) ways to determine the thread of a hub:

a. Try different freewheels (if you have; donīt screw them on all the way and keep the removal tools near)

b. Use a thread gauge (for the discerning gentleman)

c. Take three hubs, two of them with the same known thread. Strip all of them down to the hub shell. Clean the threads thoroughly with a toothbrush. Interlock the threads of two hubs in front of a light background. You will see some light through the gaps between the threads. Move the hubs slightly back and forth. If you reach a point where you see almost no light, the threads of the two hubs are the same. If you never reach a point where you see almost no light, but always see some light (i. e, distance) between the threads, the threads are different. Repeat this a couple of times until you trust the result.

`Fraid my NOS Campagnolo Record hub from Italy is French.

Thank you, everybody who was willing to help!
Oh, and if anyone has a surplus NOS 28h Campagnolo Record high flange hub shell with Italian thread, I would be interested.

Nuovo

Road Fan

I heartily second this! A digital caliper can be pretty cheap these days, same for Chinese thread gauges on Amazon. If you don’t know precisely what to look for you are just searching in the dark without tools, for this particular problem.