Hub thread on a freewheel

[Reynard]

Forgive me if this is a daft thing to ask.

As I've discovered, there are freewheels that don't take the standard splined removal tool. Not a problem, other tools and removal methods are available. But what I've in mind to do is to take a good freewheel that doesn't take the standard removal tool off one bike and use it to replace a damaged freewheel that does take the standard tool on another. As far as I can see, that part shouldn't be a problem as the hole for the axle seems to be much of a muchness. Both freewheels have the same number of sprockets and the same ratios, so in theory, it's a straight swap.

What I really want to know is whether the thread that fits the freewheel onto the *hub* is universal or not.

If it is, then I don't mind swinging for the right removal tool (tools don't go to waste, right?) and carry on as planned. If it isn't, then some thinking is required as to where to go with this project.

The damaged freewheel is a 5-speed Shimano SIS, which came off with the standard removal tool.

The freewheel I want to replace it with is a 5-speed that is stamped Falcon . Lifei Co ltd - this also takes a splined removal tool, but it needs one that is a good two to 3 mm narrower than the standard.

Any thoughts?

 

[Ajax Bay]

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

Freewheel Threading

The standard ISO threading for freewheels is 1.375 x 24 TPI

Metric BMX	1.181" x 25.4 tpi	30 x 1 mm
French	1.366" x 25.4 tpi	34.7 x 1 mm
British	1.370" x 24 tpi	34.80 x 1.058 mm
ISO	1.375" x 24 tpi	34.92 x 1.058 mm
Italian	1.378" x 24 tpi	35 x 1.058 mm
Type	Inch	Metric

All recent freewheels and threaded hubs, regardless of where made, use ISO threading. The older British and Italian standards use the same thread pitch but a very slightly different thread diameter, and are generally interchangeable.

 

[Reynard]

OK, thanks...

Both bikes are UK made. The donor bike is from 1985 and the recipient is from 1998 btw.

So if I read this right, it should be a straight swap.

 

[Ajax Bay]

Every time, on many different bikes (70s to naughties), the freewheel block has screwed onto the hub smoothly (so same diameter and pitch) . Getting the b*****s off on the other hand . . . Try screwing a freewheel hub into a threaded BB (left side) - just for a laugh

 

[Reynard]

Well, the things are essentially self-tightening. Quite an elegant solution, really.

Removing them though, is not elegant. And not terribly ladylike. I think I fried the ears of everyone within a three mile radius.

A bit of digging has turned up that Falcon freewheels do have their own dedicated removal tools. Yeah, there's more than one, and god knows which one I need. I think I may just take the wheel to the LBS and meep rather hopefully at them...

 

[rogerzilla]

If you want to dismantle a freewheel off the bike, the fact that it screws onto a BB left cup is useful, because it gives you a way to hold it with a BB tool while you undo the cone.