Recommended time for Aso

Hi there.
Since the past earthquake of Kumamoto I learned the connections to Aso is quite limited so I thought of renting myself a car.

However, I do not know how much the traffic is and road conditions, etc. I dont really trust Google maps as it directed me through the bridge west of Mt Aso that is actually gone due to the earthquake...

Doing this as a day trip, how much time would you recommend for Aso, including driving times?

Also, how is driving through Kumamoto in the early morning like? I found some rental shops west of Shinkansen station and a few in the outskirts...

90-120 minutes to drive there for slow drivers, same on the way back.

Just going for views of Asosan, maybe 30-60 minutes needed. But add house riding, touring the local towns, visit what is left of the shrine etc. It could be an all day affair.

https://www.google.com.au/maps/dir/Kumamoto/Aso+Volcano+Museum/@32.877...

Google map of route Kumamoto Station to Asosan Museum/lookout. I have included the bypass/detour road.

Local towns? Do you have any recommendations for that?

Oh, didn't know you could use to west road. I heard the mountain is only reachable from the north, perhaps that is old news?

https://www.google.com.au/maps/dir/Kumamoto/Aso+Volcano+Museum/Aso+shr...

Sorry you are correct. I forgot about the inner plateau road closures. I rejigged the google map. it says 2h04m for visting both the museum and Migaji areas. And would be less on return as you'd only go the museum once.

So the closures are only adding 30 minutes each way.

Town of Takamori for something extra http://www.town.takamori.kumamoto.jp/kankomap/kanko/yusui.html

As a reminder, since when most people think of Aso they think of the volcano, there is still a Level 2 restriction which means you cannot get closer than 1 km from the mouth of the volcano.
If you want to see what you'd miss though, you can get a good view at
https://www.youtube.com/watch?v=Tyh_nKrv5tY

If you have a car, there are numerous excellent places to visit though. Once spring is underway, the Kuju Flower Park is a beautiful place to see a large variety of flowers. The Daikanbo lookout offers a spectacular view over the whole area when the weather is clear, and the Nabegadaki Waterfall just west of Oguni is very nice as well - especially when you view it from behind the waterfall in a tunnel.

And if you want a great place to stay, there is Kurokawa with its rotenburo hot springs in the forest.

Thank you for your replies guys.

When is spring actually undeerway in that region?

Drove to Aso from Fukuoka in early December. On the way to Aso, I chose Yame route and Hita route on my way back. Stayed one night in Uchinomaki Onsen. Also drove to Kusasenri, with about 30 minutes drive from Aso station/road station area.
R3 and R57 tend to be slow within Kumamoto city.