You didn't say where in Colorado; however, I'll bet you will be going to either Denver or Colorado Springs. If it were me, I'd stay off the interstates (I-35 to I-70), and go 287 through Amarillo, Lamar then to Pueblo. Then take I25 north. Also, you might want to take some Stabil with you to add to your gas. Colorado is a very liberal state and uses junk gas. Have a great trip regardless of which route you take.
on the map looks to be 300 miles shorter to denver than the way i went, orange county to ouray, silverton, over to denver, then toured the whole state, 5 days, and not even enough time, sooo many places to see, pikes peak, steambaot springs, leadville,... historic musem i spent a whole day in the friggin musem , what a piece of history, eat some pan fried trout for me, watch out for the abundant deer, pack your rain gear, it can be nice, sparse clouds one minute, down pour the next, if you plan on staying at motels, book a room reservation, when the sun goes down most motels are full , at least in the smaller areas, which pretty much describes a lot of colorado. you can pretty much ride the whole state and never get on a freeway, last time i went was, 1996 im long over due to go again, wake up and point your front wheel in any direction, pretty much a motorcyclist dream.