Here are some formulas for manually figuring theoretical speed, actual speed, slippage and RPM:
Theoretical Speed Equals:
RPM / Gear Box Ratio x pitch x .000947 = Theoretical Speed
5,000 rpm / 1.87 x 17 pitch x .000947 = 43 MPH Theoretical
Actual MPH Equals:
Theoretical MPH ? slippage % = Actual MPH
43 ? 10% = 38.7 MPH Actual
Grip vs Slippage Equals:
Theoretical MPH / Actual MPH = Grip
43 / 38.7 = 90% Grip vs. 10% Slippage
RPM Equals:
Actual MPH / Grip% / .000947 / Pitch = ?. Then ?. x Gear Box Ratio = RPM
38.7 MPH / 90% Grip / .000947 / 17 Pitch = 2671 x 1.87 = 4,995 RPM
Theoretical Speed Equals:
RPM / Gear Box Ratio x pitch x .000947 = Theoretical Speed
5,000 rpm / 1.87 x 17 pitch x .000947 = 43 MPH Theoretical
Actual MPH Equals:
Theoretical MPH ? slippage % = Actual MPH
43 ? 10% = 38.7 MPH Actual
Grip vs Slippage Equals:
Theoretical MPH / Actual MPH = Grip
43 / 38.7 = 90% Grip vs. 10% Slippage
RPM Equals:
Actual MPH / Grip% / .000947 / Pitch = ?. Then ?. x Gear Box Ratio = RPM
38.7 MPH / 90% Grip / .000947 / 17 Pitch = 2671 x 1.87 = 4,995 RPM