Originally Posted by
anubisgrau
as we will have our backpaks on day 4 - can we leave them somewhere in mt aso as well as kurokawa?
There are lockers at Asozan Nishi Eki (Bus/Ropeway station):
http://www.kyusanko.co.jp/aso/lang_en/
Note that the ropeway is currently down for maintenance but they are providing shuttle buses up to the crater.
At Kurokawa Onsen you could leave your backpacks at your ryokan before/after checkout. If they are really large you should forward them to your hotel in Hakata from Kumamoto and travel with a small overnight bag.