Originally Posted by
thedoc46
My 'simple' cat eye trip computer which is very accurate, according to my iPhone GPS on speed, and caliberated via the circumference, always is a little higher for avg speed than what Strava gives at the end of all my rides.. I was wondering if that's because my iPhone occasionally drops off or loses the gps signal.
Starting with the concept that average speed equals distance divided by time -- which of those two factors is different on the iPhone versus the Cateye? Does the Cateye show you've traveled a greater distance, or does it show you covered the same distance at greater speed (... or both)? Or, a related question, how different are the average speed reports? The Cateye would register small side to side (even slight weaving/wobbling) motions that would not register as forward motion on a GPS track, wouldn't it? Leading to the question ... what's the case that the iPhone GPS distance is more accurate than the Cateye distance, in terms of forward motion?