AN IMPORTANT TIP FOR REMOVING FREEWHEELS!
Some freewheels have quite shallow indentations into which the removal tool is supposed to fit (yes I'm looking at
you Dura Ace!). If you put the tool in a vice and sit the wheel on top of it and try to turn it, you won't get enough purchase and at best the exercise will be pointless. At worst you'll damage the freewheel and make it impossible to remove next time. The answer however is devilishly simple!
Use a long quick release skewer to clamp the removal tool into place. As you loosen the freewheel you'll have to also loosen the skewer, but make sure you keep it tight enough not to allow it to slip and burr the freewheel.
Standard two and four prong (Suntour style) removal tools don't have this issue so much, although I do it this way with any freewheel these days. Especially if it's a hard to find freewheel like the aforementioned skip-tooth, or a Suntour Pro Compe Ultra-spaced 6 speed 13-32!
But it's the only way to do it with a Dura Ace freewheel, where the tool's protuberances are less "prongs" and more "nubs".
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