Skiing is an obvious type of extreme sport. Mountain biking has also been a type of extreme sports and is very popular across the United States. Have you thought about combining those two activities? In Vail in Colorado, skiers who are cheesed off about the warm summer period with no snow around have invented a way to get over it while waiting for the snowy season. They combine both sports and have given some off work ski-lift operators something to do. If you love biking and you also love skiing, this mixture of extreme sports is made for you.
Once the ski lifts have been opened up for the skiers, and for a reasonable fee, they will carry the skiers to the top of the mountain with their mountain bikes. They then take the ski-lift taking their bicycles with them. When they get to the top, they jump off the lift - landing on the bike's pedals with their feet and they are off. They can choose from a choice of different slopes to ride down at crazy speeds. The only difficulty is that a hill with most of the snow gone is covered with rocks and bits of old wood. These obstacles as well as the steep slopes make this sport risky and exciting - and of course - extreme!
Do not try this if you are a beginner to extreme sports! Protective gear is necessary which should include some helmet and pads. You are on a bike and not skis! The bike itself can hurt you if you smash into some rocks. The handle bars can provide nasty gashes on you. Knee pads are recommended as well as thick gloves. When you fall off your bike going upwards of thirty miles an hour, you will slide a long way - ow!
One way to stay a bit safer is to follow the normal routes on the slopes by using the standard green, blue, black, and double black diamond. It is never advisable to go off course because the barrier fence that surrounds the run in the winter will probably have been removed. Beginner extreme sports enthusiasts will find that going down ski slopes on a bike is harder than it sounds. You have to be manouverable enough to jump your tires from one side to the other to get around obstacles and to make tight turns in order to avoid a collision
Slope mountain biking can be found at Vail, Colorado and other places in that locality. Call ahead and make sure that they allow the bikes on the ski lifts. It is also worth asking how much it will cost to buy tickets. Many ski resorts are open for summer guests and they may have the lifts running for tourists who wish to ride just for the view.