The surface that caught me out was a slightly cambered, slightly rutted mud track with a bit of damp grass. The back end was sliding side-to-side all the time and eventually jumped from one rut into another, causing the spin.

What tyre pressures can I run safely? I need to be able to do 50/50 road/off-road without changing pressures as there are a lot of roads connecting the local tracks. I'm guessing that anything below 20psi has a danger of becoming unsafe on the road or causing the tyre to slip and damaging the valve. Is 20psi a reasonable pressure to try?

I have to confess, I am now monitoring ebay for a �2000 250cc dirt bike. My reason for green laning is as practise for some adventure tours on the XTR. If the XTR with me on-board is going to regularly come a cropper riding it on green lanes through the winter, maybe I won't have the mechanical faith in it come summer to head off on tour on it.