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Gear Ratio interesting

Posted: Wed Nov 09, 2011 7:29 am
by Vmax540
http://www.racenssr.com/calc.htm

MPH Calculator
Fill in the appropriate information below, Then click when finished.
Engine RPM
Chain Case Gear ratio
Clutch ratio (1.00 w/o Overdrive)
Driver diameter in inches (7.07, 7.75.) The speed in MPH is miles per hour.
The same DRIVER size and RPM will give the following speeds based on the following gear ratio changes.
1.40 1.45 1.50 1.55 1.60 1.65 1.70 1.75


RPM / gear ratio x wheel circumfrance / 1056 = MPH
gear ratio = bottom gear / by top gear example 18/33 is 1.83 gear ratio
wheel circumfrance = height of driver 7 inch driver is 7 times 3.14 = 1.666 is circumfrance
8250 / 1.83 x 21.98 / 1056 = 93.93mph
at 8250rpm with 18/33 gearing and 7 inch drivers=93.83 mph