Last year when I was heading north I planned to stay in Redding for 2 days and ride there and paddle the Lake but was 100+ degrees so was a quick 8am stop riding from Shasta Dam before blasting north to Bend. The following is probably as green as we will see it down south this year in SB.
We lived there for 5 years but never rode it as far a dirt wise. Road wise was a blast platina, hwy 32 and lason were great road rides.
Yup, spring and fall are awesome. Summer it warms up a bit, winter is usually great too except for the rainy few months. Shasta lake is looking grim but whiskey town is usually always full. Tons of fun twisty roads.....