Bicyclists and motorists share the same rights within Colorado. That means they also have the same responsibilities when it comes to avoiding collisions.
When you're riding a bike, it's important to be courteous of others. You need to obey all traffic laws that apply to other motorists, as well. Cyclists are supposed to ride on the shoulder of the road unless there is not one. If there is not one, then ride on the right side of the road, as far to the right as possible.
There are some exceptions. For instance, if you believe that the shoulder is unsafe because of debris or other issues, you may ride on the street itself. You can also ride in the street if you are planning to make a left-hand turn, since you have to place yourself appropriately to do so. You may also enter the roadway if you want to overtake a slower vehicle or if you are on a one-way road and want to ride on the other side of the lane.
While cyclists often travel in a single-file line, that's not always necessary. If the lane is large enough to allow you to ride with two people next to each other, you can do that. If there are no bike lanes, it's typically safer to ride in a single-file line.
As a cyclist, you have a right to be on the roads as long as you're traveling safely. If drivers aren't being safe or someone hits you, you have the right to pursue a claim for any injuries you've suffered.
Source: Bicycle Colorado, "Rules of the Road," accessed Sep. 20, 2017