What difference does the roller drum diameter make?
Selection of the proper drum diameter for your level of training is very important. Larger drum diameters of 4 or more are made popular by a lot of manufacturers, however youve probably noticed these are typically sold with resistance units. Large drums give you a relatively easy spin on high pressure road tires, and a little more aggressive spin on mountain bike tires. If you train on hybrid or mountain bike tires and your body weight is above 170 pounds, you may want to stick with the larger drums.
