Speedometer

[walleyejack]

Looking to update my speedometer that is toast, anolog or digital ? Can use my GPS but anything i have read says GPS is not very accurate, can be out anywhere from .05 to 2.5 mph. any ideas ?

Thanks Al

[lew]

Actually I think you'll find it's just the opposite. The speedo isn't too accurate but the GPS should be bang on.

[walleyejack]

ok thanks Lew. of course it was the folks in the guages business saying this, I havev been using my gps lately for speed control, or sometimes i just through the line over and check the spoon out and speed up or down from there,

thanks

 

 

 

Actually I think you'll find it's just the opposite. The speedo isn't too accurate but the GPS should be bang on.

[lew]

Al, you'll find the GPS really shines when your moving slow and want to maintain a low troling speed, infact their so accurate they give your speed while your just drifting along with the wind.

 

Your speedo works off water pressure and won't even register a speed until your moving fairly fast, I think my boat is close to 10 MPH before the needle moves.

[Dutch]

I wouldn't even worry about fixing or replacing the speedo in your boat. They aren't accurate at all. I'm with Lew on this one - GPS all the way, no matter what.

 

Speedos really shouldn't even be in a boat since they are so inaccurate.

[DanD]

I agree today’s GPS are vary accurate showing land speed; I use my handheld here at the shop; checking vehicles speedo’s calibration against the speed sensor’s input to the computer. If all three agree I know the vehicle is good.

But on the water it doesn’t compensate for current.

Lets say you’re trolling in current the GPS will still give you accurate land speed but you’ll have to compensate for your baits water speed; adding or subtracting depending on whether you’re going with or against current.

Running in a 1 mile an hour current with a GPS speed of 2 miles an hour; going with the current your bait is running somewhere around 1 mile an hour. Going against the current with the same GPS speed your bait is likely running around 3 miles an hour. In other words the bait’s action and speed in the water as 1 or 3 miles an hour in the current.

 

Dan.

[Roy]

With GPS being on virtually every boat, speedometers are useless. As far as I'm concerned, a speedometer gauge on a dash serves to fill an esthetic gap next to the RPM gauge. Sounds pretty crude but that's my opinion.

[fish_fishburn]

When I am doing 60 mph in my boat on gps my merc speedo says I am doing about 66 mph. How's that for accuracey.

[danc]

On a commercial flight a few years ago, I had my hand held Garmin with me. On the tv screen attached to the seat in front of me, there was a gps channel that shows just where you are and how fast you're going. My hand held read exactly the same speed as the jets more sofisticated gps system. 500 and something mph. Wanna know exactly how fast you're going? Trust your gps. Mine gives speeds within 1/10 of a mph.

[Dutch]

With GPS being on virtually every boat, speedometers are useless. As far as I'm concerned, a speedometer gauge on a dash serves to fill an esthetic gap next to the RPM gauge. Sounds pretty crude but that's my opinion.

 

Some of the bassboat manuafacturers (Triton and Ranger, I think) are no longer instaling speedos in the dash in favour of factory installed larger screen GPS units in dash. At least on the higer-end models.

 

They really are useless in a boat.

 

RPM guarge is much more important, followed by water pressure.

Edited July 3, 2010 by Dutch

[jace]

On a commercial flight a few years ago, I had my hand held Garmin with me. On the tv screen attached to the seat in front of me, there was a gps channel that shows just where you are and how fast you're going. My hand held read exactly the same speed as the jets more sofisticated gps system. 500 and something mph. Wanna know exactly how fast you're going? Trust your gps. Mine gives speeds within 1/10 of a mph.

 

I've made the same comparison. I think it was an on an MD-L1011 with a big movie display. I turn on the gps for all flights that let passengers use it and you're right, most cruise 5xx-550mph, and there were a few around 600mph. You can see my max is 604mph, i tell dumb people i did it in a car, and some believe it because you can't inject the numbers into those fields.