Magnetic Resistance Settings: The Rocking Rollers use a magnet housed in a plastic swivel-arm which is located adjacent to the flywheel. This arm is rotated in or out of engagement with the face of the flywheel to change the resistance level. Fully engaged is maximum resistance. At any given setting, the resistance also goes up with speed, so experiment to get what feels good to you. You should avoid riding at a higher mag setting than you really need. (Please refer to table below.) Speed      Mag Off    Mag 1/4    Mag 1/2      Mag Full 7 mph            110             115            140             180 10 mph          160             172            225             280 12 mph          197             215            280             350 15 mph          240             280            370             460 18 mph          300             340            460             575 20 mph          335             380            535             635                      I----------------------- POWER READINGS-----------------I As you can see from the wattage table, there is a range of wattage for each mag setting. We suggest you choose a setting whose maximum is similar to the highest wattage you intend to ride at. In other words , when possible, you should generate higher wattage through speed increase rather than by adding magnet force. This promotes higher flywheel speeds for any given wattage, which feels more realistic. As an example, if you don’t plan on riding harder than 335 watts, you should stay in the Mag Off setting and push your speed up to get that wattage. Although you could also get 335 watts from any of the higher mag settings, it comes at a slower flywheel speed. High wattages at slow speeds should be used for climbing simulation.