A new Garmin Issue

I know that many of us have moaned the issues with Garmin and its accuracy on tabulating climbing, etc. Using MotionBased and the adjustment features, I've found the results to be surprisingly accurate.

But a new problem emerges:

On this ride, you'll see a big dip at 7.5 miles and 52.5 miles:

http://trail.motionbased.com/trail/i...kValue=7872610

This perplexed me, because, while I was at the beach and knew I was "low"...I never felt that I was 25 feet below sea level (and protected by Dunes:rolleyes:). So using the analyzer, I determined that:

• this was a bridge crossing over the Perdido Bay Pass
• while I was on a bridge and my Garmin registered an altititude of 66 feet,
• MotionBased registered the topography which is the depth of the waterway under the bridge I was crossing!

So, the Garmin was accurate, but the MotionBased adjustments followed the contours and not the road/bridge elevation!

Any of you who ride in the mountains notice anything like this when you cross over a bridge?

Don't use the MB Gravity Web Service when you upload your data. I find it doesn't help when you have the Edge 305/705 which has the altimeter. The MB Gravity Web Service is for people who only have GPS and no altimeter. Because the GPS data is inaccurate when calculating elevation.

On Training Peaks web site there was a bug that showed my route crossed the Atlantic Ocean and went to Africa. Generally speaking I prefer to rely on what the GPS + altimeter recorded and ignore any "smoothing" or topo data provided by software.

Hmmm, but I thought we had to rely on the smoothing correction to get accurate climbing data...:confused::confused:

I'm feeling a little between a rock and a hard place:eek: or maybe I'm just dense and can't get it (despite my IQ of 148 - which means I'm totally clueless:rolleyes:)