



 
Hi Lindsay, The circumference of a 14 inch diameter circle is π times the diameter which is 16 π inches and 60 miles is
Hence in 60 miles the tire will have rotated 60 × 5280 × 12/(16 × π) times. At 60 mph that's
There are 60 minutes in an hour and 60 seconds in a minute so at 60 mph the tire makes
which is
One rotation is 2 π radians so finally we have
or
Harley  


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