I have been to Morocco twice. Both times the total trip was 4 weeks - about 3-4 days to get there and the same back, leaving approx 3 weeks in Morocco. Its a great place and the contrast with Europe just crossing the Straits of Gibraltar is mind blowing. 3 weeks in Morocco is enough to see plenty of the country. But Feb & March are winter months and you have to do a lot of travelling in what could be some very cold and nasty weather in France and/or Spain (esp Spain - it was 0c at the end of October in the central high plains area both times when I came back) to get to the ferries in the south of Spain (unless you put the bike on a van and either drive it down or use a bike courier and fly it down). Then there's Morocco - one of the highlights is the Atlas mountains. They get a lot of snow even down to modest levels and are very cold in winter - there are ski slopes and "snow gates" on the roads. I am not sure when their seasons change but I would have thought it will still be wintry into March. The coast and the south should be OK but you will miss out a lot of the best bits - Todra Gorge, etc. Check the climate out before firming up plans. I may well be wrong on the timing of the snow in Morocco.
I hope you have a great trip - in fact I know you will.