I carried two Sportsman 500's from about 500 ft above sea level in alabama to southwest colorado at about 7500 ft. We had no problems using them but you could tell they were sluggish. Our buddy had a honda that would barely run when we got there. We had to adjust the carb but it's no big deal your's should be fine.

Colorado has a number of specific regulations about registering OHVs (Off-Highway Vehicles, as they classify ATVs) for use on public lands. The very first thing you need to do is go the the CO DOW website and check out the information on OHVs. Even most Colorado natives don't know the rules, and a lot of people have gotten tickets--worst case scenario, some have even had their ATVs confiscated--because they were not properly registered.

Thanks don, I already have and have purchased the required permit. I have been with guys who had atv's there but they were older and smaller atv's and was just curious if they did something i didn't know about (carb issue). But thanks for making sure i looked into the permit issue. I have heard horror stories of people getting them confinscated and fined.

thanks