I've always held the bike up, just sitting on it's wheels under it's own weight - give the chain 50mm (2") of free play (on the Ten it easily touches the bottom chain runner on the swing arm).

It's a bit of horses for courses, if you have a soft rear shock, and are riding hard on rought ground then a bit more slack is needed. If you'r shock is pre-loaded up and your a motorway commuter, then a bit tighter. I tend to keep the TTR (Green Lane bike) to about 60mm of play, a bit more than the manual advises, but there is a decent chain guide at the rear end so thats OK. Maybe worth looking to see if the TTR Chain Guide will fit the Ten, most of the other stuff at the rear end is the same......

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