My wife and I have Masi road bikes about 10 years old. We are in our early 70s and ride 100 miles/week at most (usually less). The original tires look brittle so I'm planning to replace them. The tires that came with the bikes had no tread but I was thinking about getting new tires with some tread for better road traction. Also would these allow for some use on dirt or sand? I'm looking for recommendations for new tires (size 700x23). Should I replace the tubes also?