Is the CO Sand Dunes open for riding?

[HomeMadeSin]

Are the Great Sand Dunes protected from motorized travel?  I'd love to fire the CR500 up on the dunes and thought since the tire, sprocket and chain need to be replaced, I'd just as soon hred the last bit of life from then on sand.....

 

[tx246]

those are some impressive dunes in the national park. ive footed to the top of them before. i dont know if there is any orv riding available or not though.