Beware of using Google Maps to plan your route, firstly it is extremely optimistic on timings (add at least 25%) and secondly the road numbers were never changed when Morocco renumbered the roads in 2018. Apple Maps and OpenStreetMaps have the correct numbers. Get a copy of Reise KnowHow map from Amazon as this has both old and new road numbers on it.

Travel in Morocco is slower than most people realise. Although the speed limits are roughly similar to the UK they are most severely enforced with radar guns and on-the-spot fines.

Don't bother riding into big cities (Fez, etc) unless you are planning to stop two nights otherwise in the evening you will be fighting your way through the worst traffic you've seen, only to repeat the exercise the next morning on the way out.

To get going quickly on the first day you might want to consider coming south down the A5 coastal motorway then east on the A2 to Meknes, then south east to Azrou (stop overnight Hotel Panorama). That's a 5.5 hour ride plus stops.

Your second night could then be Erg Chebbi sand dunes near Merzouga (Hotel Kanz Erremal), about 7 hours riding plus stops.

Third day visit Todra and Dades gorges with an overnight at El Kelaa M'Gouna (Kasbah Itran), probably 5 and a bit hours plus diversions into the gorges.

Fourth and fifth nights in Marrakech (Hotel Ali ?), six hours plus stops.

Then on day 6 take the motorways back to Tanger, 7.5 hours plus stops. That's a grand total of just under 2000 km.

As for planning your day, first light is about 07:15, sunrise about 07:40, sunset about 19:00, full dark at 19:25. So 12 hours between sun up and sun down.

I always start with just coffee and juice at first light, then have breakfast at first stop.

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"For sheer delight there is nothing like altitude; it gives one the thrill of adventure
and enlarges the world in which you live," Irving Mather (1892-1966)

Many thanks Tim (and all the other respondents) for taking the time to give me some feedback. Some great ideas and hotel suggestions that we will definitely use