My friend and I are going to take the enchanted circle drive and go clockwise so if we wanted to hike the trails in the Cimarron Canyon State Park and it's after 4pm, can we still do it or have to come another day?

Yes be careful out there.

Say hi to the bears!

I'd say yes! Plan accordingly in line with sunset and you will be just fine. It is a beautiful drive and there are plenty of nifty stops along the way. I dont think Red River is considered part of the circle but if you haven't been there before it's well worth the stop. The locals are really friendly. I've taken this drive more times than I should admit. Its addictive! Have fun, be safe and remember to pack some extra water.