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...because I, too, have experienced the alarming shortage of 5 an 6 cog freewheels, in the 14-26 and 13-24 ranges that I use on a lot of things I own, I have been forced (by necessity), to start re-cogging some, using scrapped freewheels from the co-op as my source for cogs. The Suntour freewheels are really good for this purpose, because there are a lot of them in the used parts stream that still have cogs that are not worn out.

But the only way I can get them dismantled most times is by using a mix of acetone and ATF as my penetrating oil. Even then, I often need to heat them with a MAPP gas torch. I'm certain this is not what ATF was designed for, but it sure works well.

As for writing off Suntour freewheels as beneath your dignity, I can only refer you to the prices commanded by the 14-26 five and six cog ones on ebay currently. I do Shimano 6 cogs too, with their better shifting cogs, but the earliest ones in five speeds have an annoyingly small center hole, which will almost, but not quite, fit over a campy hub lock nut. Which is a PIA.