Electronics, Lighting, & Gadgets - Wheel Circumference Measurement for Garmin Edge 500

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Tall Cool One
04-26-12, 09:41 PM
I am in the process of setting up my Garmin Edge 500. I have a 700c wheels and run 25 mm Continental GP4000s tires. My best effort at measuring the diameter of these wheels was 680 mm. Hence, the circumference would be 680 x 3.14... which comes out to 2136 mm for the circumference. Is that within the proper range for this setup?

Giro
04-27-12, 09:24 PM
Better yet, take a bike ride on a measured course and use the late, great Sheldon Brown's method (http://www.sheldonbrown.com/cyclecomputer-calibration.html#measuredmile). Google maps and the like make it relatively easy to set out a measured course and you get probably the most accurate calibration for your weight, tire, pressure, and courses you will ride in the future.
znomit
04-28-12, 12:10 AM
The edge works out the wheel size for you using the GPS.

mechBgon
04-28-12, 12:15 AM
Alternately, just measure the effective circumference the obvious way: mark the tire, line that up with a mark on the ground, sit on the bike and roll it forward one revolution. Make a second mark on the ground where the tire's mark ends up. Measure the distance between the two marks.
Shimagnolo
04-28-12, 12:26 AM
The edge works out the wheel size for you using the GPS.

^This.