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The Sirius is a striking cycletrainer with an ergonomically shaped frame that rebounds slightly while you ride. The magnetic brake contains two discs, each of which is equipped with six permanent magnets. You can use the 10-position lever on your handlebars to shift the magnets' position inside the brake unit in relation to one another. During your work out the power increases when you speed up and/or shift to a bigger gear. The Sirius is equipped with a finely balanced steel flywheel that weighs 2 kg to allow for a fluid pedal stroke.