^^^ Much better than a rag.I made a chain whip with a piece of chain and metal ,it didn't cost anything.
Cassettes can actually move like that due to a loose lockring, some freehub body/cassette combos more than others. I've seen a lot of loose lockrings too, though that one must be extremely loose if nothing else is wrong (missing spacer, etc.). Some people tighten them with their fingers.that sure appears to be a worn freehub...especially if the hub is aluminum. The cog movement is front to back. If it wobbled side to side, a loose lockring or missing/mis-placed spacer could be the culprit, but I have never seen a lockring loosen up if tightend even close to spec. Has it been apart recently? It really don't make any difference, either way it's got to come apart.
really??...with their fingers??...OMGCassettes can actually move like that due to a loose lockring, some freehub body/cassette combos more than others. I've seen a lot of loose lockrings too, though that one must be extremely loose if nothing else is wrong (missing spacer, etc.). Some people tighten them with their fingers.