Hello JB,
There are different possible iteneraries for your eventual trip to Ethiopia, depending on your preferences.
One of the possibilities would be the historic route to the north of the country:
starting from the capital Addis Ababa to Bahir Dar, proceeding to Gondar, Debark wich is situated at the entrance to the Semien Park (I dont know if motorbikes are allowed in the park), Lalibela, and either back to Addis or, depending on your schedule, visit some of the churches in the Tigray region of the country.
Other possibility would be the south:
Addis to Arbaminch, Konso, Jinka, Turmi, Konso, Yabello, Yirgalem, Lake Langano and back to Addis.
Mind you, the condition of the roads for the northern itenerary is quite good, mainly paved roads, except for the part from Gondar to the Semien Park, and Bahir Dar to Lalibela wich are garvel roads.
For the southern itenerary, about 50% of the roads are under contruction, so often you will find temporary gravel roads.
It is safe to travel in the country, especially in the above mentioned iteneraries.
Regarding rentals of motorbikes, there is only one agency doing this, it is called African Riding Adventures, they have their own website.
Good luck,
WM
| 
Réseau Inc.
