GPS Problems?

[D&D]

I have a (new) very popular Garmin GPS device and use it each time I run. I have posted several times that I am in search of 60mph with my Mean Machine, but that I keep running 57mph. I have spun out and crashed several times (quick spins, etc.), but always 57mph.

OK, here is the facts, yesterday I am running my boat and it looks like it is really moving, great attitude and all, but then I had a quick half spin out. The boat stays up right and I continue to run. I get the boat back, open the lid, and the GPS is reporting 68.8mph - and yes, the "max speed" and "trip data" were reset to zero before the run.

Now the boat looked great, but most every run it has looked very good to me. Has anyone experienced a run where your GPS just seemed to be out of wack with your previous experience with that boat and GPS? I have used this GPS previously on a car trip and it matched my digital speedometer in the car.

[keithbradley]

Im not sure what causes the glitch, but it does seem to happen from time to time...At least I hope its a glitch...It wouldn't be safe if my wife really WAS driving 200mph with the kids in the van!!!

[knpc]

I put my Garmin GPS in my boats every time also. In a given setup the top speed is always the same (within a mph or two), but if the boat blows over I have gotten some bad readings. A boat that does 60 every time out comes back with a reading 87, either the flipping or the impact throws off the speed readings.

[D&D]

WOW that's faster than my wife's 84.5 mph, but in my wife's case the gps was giving a correct read!!!!!!

[D&D]

OK, so it does happen to others. I have had two gps devices and never saw a reading from them that seemed to be off, so I was quite amazed at that reading. Hey, a guy can dream can't he?

[blackcat26]

I have had some bad readings also from some tumbles. As far as I can tell sometimes the motion of the blowover etc. is faster than the boats speed for just a moment.

[D&D]

Wait a minute. Who says the rules are "that speed counts only when you are going in the desired direction"? There you go then, I finally hit 60mph and more. Now let me see, how can I have a more serious (faster) accident - maybe I can hit 70mph!