A traditional freewheel cluster has matching threads which screw onto the hub. This is different from the more modern " Freehub ® " or "cassette hub" design, in which the freewheeling ratchet mechanism is a more-or-less integral part of the hub.

Jun 5, 2014 · The ISO freewheel thread standard is 1.375" x 24tpi. Most freewheels I have encountered have been ISO. Some hubs use "British" threading at 1.370" x 24tpi. If you use an ISO freewheel on a British thread, it will work, but you should check there is enough thread engagement to avoid stripping the hub.

Budget-friendly, general purpose freewheel. Freewheels shown on this page fit the threads of all standard freewheel hubs, with the exception of some older French hubs that used a different size .

On most freewheels, two or three outer sprockets are threaded, and unscrew. The inner ones are splined and lift off once you have replaced the threaded sprockets. Keep track of the order of the sprockets and spacers as you remove them. The inner sprockets of older European freewheels are left-threaded and come off the back!

Vintage freewheel threading and specs on Peugeot, Motobecane, and other French bikes: here is a page of freewheel specifications.

There are 4 freewheel threads - BSC (aka English), Italian, French, and ISO. BSC and Italian threads are very close - but not the same. They are so close, in fact, that hubs as well as freewheels can be threaded so as to interchange with either and that is …

Threading an Italian thread freewheel onto an English thread hub (or vice-versa) will deform the softer aluminum threads on the hub, so it's consider a "class B fit." As long as you don't go back and forth between matched and unmatched freewheels, it shouldn't be a …

Jun 15, 2005 · Measure the outside diameter of the hub threads. Use the flat portion of the jaws so you can measure squarely and without either jaw slipping into a groove. If the size is about 1.378" (or 35mm), then clearly you need an Italian threaded freewheel.

Nov 16, 2017 · How to remove and install threaded freewheel systems as well as single-speed BMX/freestyle bikes.

Freewheels are fitted to threaded hubs – and should not be confused with cassettes which normally fit on splines. All freewheels are English/Italian threaded unless stated otherwise – English and Italian freewheel threads are to all intents and purposes interchangeable.