Good advice from Andrew and clarification from Ali B.
Most of the Sahara is gravel, not soft sand which cross-routes avoid where possible.
But it only takes a few metres of soft sand to flip a bike as you can see below.

When I met Al Jesse* in Senegal in the mid-80s, he'd just crossed the Sahara the same way I had: Tam-Agadez, but 2-up on an ST (lightish BMW boxer road bike).
Back then it was 600km of sand and gravel - now it's 220 (currently closed).

As he says "Our worse day was from the [Niger] border towards Arlit [200km], 4 miles in 10 hour day. We had 10 gal. Water and 15 gal gas."
Four miles is close to my all-time-low on a bike in the Sahara and I can tell you, you end the day barely able to lift a spoon.
I think Al was a skilled off-road rider and this - plus tyre pressures as mentioned - makes a huge difference.

The problem with bike riding in soft sand (I read once) is the in-built 'forward-pointing' castor effect of the steering geometry (desirable) gets eliminated as sand builds up in front of the wheel. The wheel wants to flop to the sides so the answer is to gas it, raise the front end + gain momentum. That's fine on an RM250 or even a Tenere, but with half-a-ton of GS12 + gear + unpredictable passenger movements, it becomes dangerous, not least because that weight landing on either of you is what usually causes the injury, not the falling off (which is often a form of relief).

Even without a passenger it can end like this (an R80 morning after in the Laouni Sands about 100km north of Niger border - now sealed).

IMO the worse terrain a bike must manage are twin sandy ruts with rocks or bushes on either side so you can't break out. Like the Gao-Tim piste (too risky these days) or indeed the French Line in the Simpson, old Gunbarrel or Telegraph Track in Au.
Tam-Agadez was not like this, it's a wide open plain, but even here you end up either paddling at 4 miles/day or as pictured below (Route A6, KM628 west) because the ever-changing terrain which you were blasting over to avoid getting stuck catches you out.

That's the nub of it on a bike in soft sand: you need to go fast to gain stability and maintain momentum, but that will soon catch you out on 500 kilos of GS/AT/CBX and pax. So you paddle at 2kph at which pace in the Sahara your water supply (time) becomes as critical as fuel (distance).

Ch

*Al went on to steal my luggage idea and became a millionaire

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Morocco Overland 4 (2025) • Trans Morocco Trail

Thanks for the detailed advice and as you say it would come down to time and distance. On that note, is there a good supply of fuel and water through Algeria-Niger (arlit) route? What would be the minimum amount of Fuel and Water you would carry should you do that same trip again?

It's an important (if not the most important) consideration as fully loaded the main weight ends up not being the bike itself which is a meer 220kgs but the fuel (22L), oil (5L), water (10L), passengers (160kg) and luggage (80-90kg) which takes our overall weight up to a whopping 490kgs!!!

This causes us to be top-heavy and then steering in sand also becomes a problem especially with tail-steer or bum-steer which can cause the rear of the bike oscillating to destabalise the whole bike throwing it from side to side and eventually loosing control.


I don't sense any built up resentment between you and Al, none at all.

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TurboCharger + Francois (our BMW R1200gs) '07
www.riding2up.net, blog.riding2up.net

Hi,

>On that note, is there a good supply of fuel and water through Algeria-Niger (arlit) route?

I don't know when you plan to to the trip, but actually the border Ain Guezzam to Assamaka is closed for tourists. And anyway crossing northern Niger exposes tourist to very high risks (see other threads in this forum).
Algeria-Tessalit is even worse thees days.
There is a sealed road from Tam to Ain Guezzam. Petrol in Tam, Ain Guezzam (somehow irregular supply, but a few ltrs for a bike could always be sourced) and in Arlit.
I would go for 20-25l of water (2 persons), 40-50L (min. 600km range with worst case consumption) of fuel and 40kg of baggage.

Regarding heavy BMW at 2 in sand I remember a German guy, fantastic driver, I met in 94 in the Erg Issaouane, near BOD. He mastered deep sand at 2 even better than is solo friend! Be prepared to establish skills by training, take a break when you get tiered.
BTW, the BMW in question had very low center of gravity due to special fuel tanks and up to 90 ltrs of fuel capacity.

Good luck,
Yves

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Yves

I met 2 French couples on GS's in Morocco, and they paddeled along on the sandy streches. Very tiresome and not pleasent for the wives.
YouTube - zagora-foum zguid

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http://tony-ontheroad.blogspot.com/