The most favorable benefit of aluminum frames is their weight. An aluminum frame can weigh up to 5 pounds less than a steel frame that measures the same size. Of the lightweight materials such as carbon and titanium, aluminum is the least expensive. Aluminum is also rust resistant, making it a good choice for wet weather conditions. Aluminum frames are stiff, which means you will feel all the bumps in the road. They are also less durable than steel frames. Whereas steel can be repaired, even slight damage to an aluminum frame can ruin it.