>I listen about stamp to passport about moto
you will get a "Feuille de passage sous douannes" valid for a few months, I suppose 3.
In theory it would be possible to "park" the bike at a customs office for an unknown fee.
I know that this fee in Tunisia is very, very high, don't know its amount in Algeria.
I would prefer to fly my bike home or the park it in Westafrica were this is simpler and cheaper.
I don't know if this is relevant for you: traveling in Algeria on a motor bike it will be hard to avoid a permanent guide (with car); in the Sahara it is even impossible, which could limit the time of your stay in Algeria anyway.
Best regards, Yves