there should be a little play in the throttle tube.
I've taken to having a bit more than the manual states as I'm used to ridding my Super Sherpa that's set up for offroad with loads of free play on the throttle tube.
You don't want zero play as the slightest movement of the hand, say going over a small bump will have the bike lurching all over the place.
Fuel injection systems likes smooth motions and a bit of slack to take up with the cables other wise you end up with a fuel On/Off switch not a throttle.
The info for adjusting the throttle cable in in the owners manual in the INSPECTION AND MAINTENANCE section. Section 7 in my K6 Manual. (procedure will be the same for all models)
Here- Page 79
http://www.v-strom.co.uk/downloads/DL650AK9OwnersManual.pdf(thread title says throttle Body Play- that's a whole different part of the bike and if you have play there you have big problems!)