Thursday, August 21, 2008

Let's do maths on cycling

Constant
I'm running 26" wheel with 1.5" semi slick tyre on my Spesh thus,
Wheel Circumference = 2010mm

Variables
At average I can pedal about 70 to 90 revolution per minute thus,
Cadence = 70 to 90 rpm
Crankset's chain ring,
Chain ring = 22/32/44 teeth
Cassette's cogs,
Cogs = 11/12/14/16/18/21/24/28/32
Gear ratio = Chain ring divide by Cogs

Question
If I pedal at 80rpm for 1 hour with chain ring 44t and cog 12t, how far can I go?

The calculation
Wheel Circumference = 2010mm = 2.01m
Cadence = 80rpm
Time = 1 hour = 60 minutes
Chain ring = 44t
Cog = 12t
Gear ratio = 44/12 = 3.67

Answering the question on how far,
Distance = Velocity multiply Time
Where Velocity = Cadence multiply Gear ratio multiply Wheel Circumference
which is equal to 80rpm multiply 3.67 multiply 2.01m = 590.136m per minute
Thus Distance = 590.136m per minute multiply 60 minutes = 35408.16m = 35.40816km

Answer
35.40816km

No comments: