Great report Tim. Plenty to see if one looks closely.

Wrt to ‘overnight sand compacting’, a German Ergoholic explained to me once that – car or moto – it’s actually down to overnight tyre cooling, though the impression is the same. Static tyre pressures can increase by up to 20% over the course of a hot day on the piste, making them less effective in sand. A heavy 4x4 on saggy ‘overnight’ tyres will be more effective – a relatively light bike much less so, especially on stiff Mich Deserts and the like.

It's commonly mentioned but away from the less arid desert fringes where dew can occur (like Mk), I’ve never noticed a sand crust firm enough to make any difference.

Not surprised to hear an unloaded KTM 450 is a gas in the sand. Light weight is the key on a moto on loose surfaces: knobbly tyres help but it makes it physically easier for the rider to react to slides and other deviations in the wheel tracking.

Well in that case… Another factor worth mentioning with motos in soft sand is the sand that builds up in front of the front wheel rather like a bow wave in water. This has the effect of messing up the machine’s self-centring steering geometry: the caster effect is reduced or even reversed (first pic below - riding downhill, admittedly). Result: bars flop to the side and over you go. That’s why on soft sand it’s so common to fall over (usually harmlessly) as you either pull away or slow to a stop (brake gently).

Once on the move the speed and the momentum that comes with it all help, but of course on a 250-kilo bike that takes some nerve, especially in dunes. That XRL in the bottom pic was close to that weight but shows a good stance: weight back; on the gas. Knees pressing into the seat/tank also makes a huge difference when standing – the 3rd point of contact ‘triangulates’ your body with the bike and helps stability.

Low tyre pressures make a huge difference but I have the same view as Tim when riding alone on desolate pistes. Unless you are ’44-second man’ avoiding punctures trounces traction - and Morocco is barely sandy anyway . Keep pressures high and let the tyres’ knobs do the work, not the contact patch. In a car it’s different.

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