Hey Kav,
There are some great places to ride during that time period. In fact, that's the primo time. What part of the state are you gonna be in? I'll probably be up there during that time period on my annual Rampart Range trek. Spark arrestors are required as is an ohv registration sticker. The sticker is $15.25 for a year. Call the Colorado State Parks Office at:
(303)791-1920
Ask them to send you a registration application. Also ask how far behind they're running.
You can also get the sticker in person at their office at:
Colorado State Parks
13787 S. Hwy. 85
Littleton, Co. 80125 (at the SW corner of Santa Fe and C-470)
Get back to me where in the state you're gonna be visiting and I'll come up with some suggestions.