Pulley Calculator. RPM, Belt Length, Speed, Animated
and you need to find Pulley 2 size to spin it at 500 RPM, enter Pulley 1 = 6, Pulley 1 RPM = 1000, Pulley 2 RPM = 500, and hit Calculate to find Pulley 2 diameter. Multiple Pulleys - RPM Reduction. To calculate multiple pulley sets, where the first driven (large) pulley shaft drives the second driver (small) pulley, and so on, enter first ...