Originally Posted by
Weatherby
I took my Garmin 800 out of a maiden voyage tonight and the speed display fluctuates wildly (jumps around by 1-2 mph) when in fact my speed was not changing as indicated by the seat of my pants and my cyclecomputer. No, I don't have the stupid cadence meter. Lots of other annoying features.
If you don't have a cadence meter, there will be a data lag because it takes time for the info to reach from the satellite to you. A cadence sensor is by far the most accurate way to measure both speed and distance.