First, you should have one of these, if not that's ok.
Off of 9, a few miles before Virgin turn north on Mesa Rd. This starts as pavement and will turn into dirt. Mesa Rd will intersect with Kolob Reservoir Rd(all pavement) up to Kolob Res. Great small road! Don't go past Kolob Res., turn around and come back to 9.
South of Rockville is the Smithsonian Butte Rd(dirt) with some nice views. In Zion, make sure you ride up through the tunnels out to Hwy 89(Mt Carmel). Nice stop at MC, with plenty of eats and fuel. Thunderbird Lodge is a popular spot, at least for pie anyway.
A bit north on 89, and west on 14 will get you up to Cedar Breaks NM.
Toroweap, has a couple of ways to get down there, directly south out of Colorado City is shortest. I was there last Thurs in my Jeep. 60 miles of dirt one way. But this is what you get...