Start at the 4 corners (where UT, CO, AZ, NM meet). It is a great experience. Take Rt. 160 to Kayenta, UT. Then take Rt. 163 through Monument Valley. It is beautiful experience. Backtrack on Rt. 163 to Lake Powell, by way of Rt. 160 to Rt. 89. The view is just incredible! From there take Rt. 89 to 67 to Grand Canyon North Rim. Make sure you call ahead for a room; they fill up quickly. The views are amazing. Backtrack on Rt. 89 to Bryce Canyon National Park via Rt. 12. Bryce looks like castles below you. Take Rt. 12 from Bryce to Zion. Take Rt. 89 to Rt. 9. Riding into Zion, you'll see spectacular scenery. Drink plenty of water; trust me it helps with the high dry temperature.