THere's no problem riding on dirt at with road tyres. You just treat the dirt a bit like a wet road ie. hang loose, anticipate and do things smoothly. The only other thing is to allow the bike to move around under you a bit and if the dirt is technical i.e. deep wheel ruts, very stony/rocky you may want to stand up on the pegs and help the suspension and balance. It's very like doing car park riding, tight turns, slow speed and use your body to help balance the bike.
On the mud is a different thing, especially good ole aussie clay. When wet this stuff is both ***** and slippery. Wheel ruts aren't deep but are even slipperier at times. All you do is keep it slow, even and smooth throttle and hope you don't dump it :-) Slippery dirt or mud is like ice except you can see it so it's good training for winter riding :-D
The causeway we did was about 60ft long followed by another 10ft of further water over the road. First gear about 3500-4000 RPM, slip the clutch, get some momentum and no matter what the bike does beneath you keep it upright and moving forward. If you decide to do a difficult piece of terrain or water or whatever, you just have to commit to it and do it. Second thoughts will mean you'll come unstuck :-) Obviously that doesn't mean blindly go through water that you don't know how deep it is. That's why I let Steve go first :-D
I've had the Sprint and the S3 up to 120kph on dry dirt no probs, the old TDM900 up to 160kph on the road from Sandy Hollow to Bylong. All on road tyres.
Here's some pics of the poor wee beastie before I washed her:
Russ
