Hey all - I just have a quick question. So, I have a French threaded hub here. I picked up a very nice Regina corn cob freewheel today (13-18). I didn't know if it was English or French thread, so I threaded it on to the hub.

Well, being the major idiot I am, I threaded it on too far. So, my question is this - if I thread an English freewheel onto a French hub, would there be actual play between the different thread pitches? Noticeably? Because, if not, it would appear as if the freewheel is French - it threaded right on with no fuss and isn't moving around...

Thanks!

The difference between English and French freewheel threading is sufficient that you'd know it if the components were different. You'd never screw it on all the way by hand.

No expert here but lemme see if I can think this through. French threaded hub should be 34.70 mm X 1 mm pitch. English is 1.370 inch X 24 TPI pitch. If you convert the English to metric it would be 34.799 mm. Real close to the diameter of the French hub but the problem is the pitch. French is 1 mm, which I think would make it roughly 25.4 teeth per inch in conversion. I think. Not close enough to 24 TPI to work, I wouldn't think. I would say you either have a French freewheel or a French hub with English, or Italian, threading on it, and an English or Italian freewheel. Am I making sense? Some experts may get in here to correct me. One question though, what do you mean by you threaded it on too far? If it fit on there with no fuss and isn't wobbling around, I would think you're OK.

Many times BSA freehweels will thread on becasue they're slightly larger in diameter but get tight as they're threaded on due to differences in threads per inch and thread pitch. Sometimes they work, sometimes they dont.

rootboy: too far as in "too far for me to take off by hand because I don't have the proper tool."

Jim: So, it's possible that even though there isn't physical play between the hub and freewheel that the freewheel still might be BSA?

I know the hub is French thread because the last freewheel to come off it was French Thread.

So my Campy hub with "1370 X 24 TPI" stamped on it, will work with a Shimano freewheel.

That is correct. Sometines it comes down to the total number of threads. If the hub has 3/4" of thread and the freewheel has 3/4" of thread there's a better chance of it working than if the hub and freewheel both have 1" of thead.

If the Shimano freewheel is BSA thread it will.

yes, but, but, but....

How many non-BSA threaded freewheels would Shimano have produced?
Or - Where are freewheels labeled?
I've never looked at mine.