If you want a set of 4-wheeler front tires that will really dig in, get a pair of Rat Dirt tires and take your 4-wheeler to Colorado's Government Trail.
At just over 10 miles, the Government Trail is a good run for the 4-wheeler rider of moderate skill level. The trail opens during the summer and closes during the winter, and it is multi-use trail that has other 4-wheeler riders but hikers, bikers and motorcyclists as well. To get to the Government Trail, take Highway 82 for half a mile west of Aspen and then take a left into Maroon Creek road. Take a right once on the road and keep going until you get to Iselin Park. The 4-wheeler trail will be visible on the right in the back of the tennis court.
Once you are at the 4-wheeler trail, remember to practice good trail etiquette, even if someone else doesn't, make sure that you do and they might just learn something from your actions. Also, keep in mind to treat the land with respect, and do not deviate from the trail at any point or you risk a hefty fine that can rival the cost of your 4-wheeler. The 4-wheeler trail begins at Maroon Creek and from there you tread across an old-fashioned wooden bridge and head into some steep terrain which will force you to climb upwards. Your Rat Dirt tires will really show their stuff on this part of the 4-wheeler trail.
This is the hardest part of this 4-wheeler trail. After the steep climb, the rest of this trail should be pretty smooth for the average 4-wheeler rider. From there you will guide your 4-wheeler over a changing environment that includes beautiful aspen, thick pines, and simply picturesque meadows full of ripe flowers. Bear in mind that this 4-wheeler trail isn't a loop so once you're at the end make sure you have a car shuttle waiting or a ride back because the trail is only one way.