http://www.parks.state.co.us/parkspa...sPassInfo.aspx
Looks like an annual $70 "vehicle" pass would be your best bet. That way if you happen to rack the bike to your favorite park or go to another you'd be covered. $3 a pop would add up pretty quickly.
I'd call 'em up and see if there are any other specials that might apply.
Good luck on the weight loss and going USAF. I'm retired myself. Middle son will be arriving at Ft. Carson, CO, in May. He's Army.