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I've had 2006 Level 4 Gl1800 for several months now, but I just now started getting acquainted with the GPS navigation system. I think I'm going to like it, but it appears that the 2006 Wings don't display speed from the GPS. I keep seeing you guys quoting speeds from your GPS system. Is this a recent change? Is there some trick to getting the GPS to display vehicle speed?

Glen
 

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All of those guys are talking about after market GPS that they have mounted.
 

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It doesn't show up on titanium wings - sorry to tell you.
 

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It is hell riding an old '02 and reading about all of these new fangled '06s and '07s with heated stuff and GPS. Am I to believe the Gold Wing GPS does not show your speed? Does it show altitude? Miles traveled per day and/or tank of gas? Total trip miles? Elapsed time, trip and moving? I know it shows routes, etc. How much extra is the GPS? Can it be updated/upgraded?

Guess my raggity old Garman 276C will have to do. I also move it to my motorhome and truck when needed. Garman sends me free upgrades, I just bring my 276C in and plug it in to download...how does this work on the GW GPS. Is it hard getting your scoot into your computer room for updates?

Just pulling your chain a little guys. Don't flame an old guy or I will call the guys in black at AARP. ha ha
 

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Yeah, if I had the Honda navigation system I would probably still have a GPS mounted on my handlebar. That thing is way too expensive. I wish you could get ABS without it.
 

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all i can say is my non Honda GPS does show speed but whats it good for when the bike already has a nice easy to read speedometer ?
 

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This is the first I've heard about the OEM Nav system displaying speed, but if it does, it would still be the speed shown on the speedometer, which has been proven to be inaccurate.
 

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Glockjock said:
I've had 2006 Level 4 Gl1800 for several months now, but I just now started getting acquainted with the GPS navigation system. I think I'm going to like it, but it appears that the 2006 Wings don't display speed from the GPS. I keep seeing you guys quoting speeds from your GPS system. Is this a recent change? Is there some trick to getting the GPS to display vehicle speed?

Glen
Glen,
To answer your exact questions: You will like the nav once you get familiar with all it's specific features. Being a built in model the nav system does not include the ground speed to eliminate display redundance. Everyone talks about this subject so much because most previous older models had reported significant speedometer inaccuracies of up to 5%. This was evidently greatly reduced on the 06 and 07 models because most late model GL owners report around more of a 2% variation which is more acceptable. Finally, personally mine falls into that 2% margin which is tolerable for me. Terry
 

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Teaser 1 said:
This was evidently greatly reduced on the 06 and 07 models because most late model GL owners report around more of a 2% variation which is more acceptable.
2% would be very acceptable, that would be
indicating 30 and actual of 29.4
or
indicating 66 and actual of 64.7

but it does not appear so on my 07 ...

My 07 with stock Dunlop tires:
indicating 30 ... actual (from GPS) = 27 ... about 10%
indicating 66 ... actual (from GPS) = 62 ... about 6 %

Should be linear (or so I thought) but it is not on my bike.
Could have just been that day ... I'll check again soon with some new GPS software I just purchased.

Measured with a 12 chan Garmin that is usually accurate to within 1mph.

Dennis
 

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Like IWING posted, Honda does not like competition. So no speed readout on the Nav models from the GPS.

:roll:
 

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Silverback, I believe the GPS unit uses the satellite to determine ground speed versus the speedometer on the bike. Most Honda bikes have this built-in inaccuracy as reported above, including my Silver Wing. I hardly ever glance at the bike's speedometer anymore, just check the Garmin 2610 that is mounted on a Texelent Bar right in front of me for easy viewing.

Mesquite Bob
 

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cycledude said:
all i can say is my non Honda GPS does show speed but whats it good for when the bike already has a nice easy to read speedometer ?
You got it! Why would Honda put two speed indicators on the bike THAT DIDN'T AGREE WITH EACH OTHER?
 

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The reason the GPS doesn't indicate speed is because it's not accurate.

"What did you say Rastoff??? Are you out of your mind?!? The GPS signal is accurate to +/-1X10^-14 (for the layman that's +/-.00000000000001 seconds) how can you say it's not accruate?"

Alright don't get your panties in a wad. When it comes to time and position the GPS is second to none. However, when you are moving it's another story all together. Let me explain:

The way a GPS indicates speed is by simple math. It takes your current position and subtracts the previous position to determine how far you traveled and then uses the time it took to get there to calculate speed. The actual propigation of error in this formula depends on how accurate the position is and how accurate the time is.

We've already determined that the GPS time is much better than needed, but the position accuracy depends on satelite signals aquired and strength. The best position accuracy I've ever seen on a WAAS enabled GPS was 9ft. Usually 15ft is more common. At 50MPH that positional accuracy is good enough, but at 5MPH it's a significant source of error.

OK, all that aside, there is another error associated with GPS and speed indication; position updates. The comercial "off the shelf" GPS only updates itself once every second. This means that it gets your position then waits one second and gets your position again then calcualtes speed. That also means that, if you're moving, it is always one second behind. So, the speed you see displayed on your GPS is not the speed you are traveling, it's the speed you were traveling one second ago. Because you can change your speed a lot in one second, the GPS is not a good replacement for your dash mounted electronic speedometer.

Don't believe me? Try this: Get moving until your GPS indicates 20-25MPH. Then come to a quick stop (be careful). You will see that when your bike has come to a complete stop the GPS still indicaes some speed. Then about a second later will indicate 0MPH.

I've mentioned this test several times on this board and no one, besides me, has ever reported trying it. Nevertheless, it's the truth and it proves why you shouldn't rely on the GPS to indicate speed unless you are traveling at a steady rate.
 

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Well I don't know about gps accuracy but down my way traffic enforcement divisions set up little trailers along side the roads that radar you and display your actual speed. I assume they are as accurate as other radar equipment thats being used. My 06 speedo is almost dead on with these, maybe I'm one of the fortunate few. Terry
 

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Don't feel too lonesome Rastoff! I've done that. My previous Garmin, an eTrex Vista, had a longer sampling window and a slower sampling rate; si it was like you describe; cruise at 70 and come to a stop and it took a few seconds to average down to read 0. My present Garmin unit, a 2370, seems to have a shorter sampling window and a faster rate of sampling and it changes so quickly that I do not percieve the lag when I have a good signal. The other situation in which that seems to have made a difference is in vector error; ie., plotting the speed while navigating curves. The eTrex was fooled by that situation and reported a lower ground speed; but the new unit, although it still likely has the error to some extent, reports a speed consistent with the now calibrated speedo of the bike.

I suggest using a speedo correction device to calibrate the speedometer to be accurate. If you use the GPS as the calibration reference, get out on a nice straight stretch with wide open view of the sky.

prs
 

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Teaser 1 said:
Well I don't know about gps accuracy but down my way traffic enforcement divisions set up little trailers along side the roads that radar you and display your actual speed. I assume they are as accurate as other radar equipment thats being used. My 06 speedo is almost dead on with these, maybe I'm one of the fortunate few. Terry
I imagine they are no more accurate than their calibration. There is one in a construction zone in a nearby town that seems to over estimate vehicle speed a good bit.

prs
 

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Rastoff,

I used to make the same argument as you. If you're traveling due north at about 60 miles per hour and the gps is updating every second then you should have traveled 88 feet in that second. However, civilian gps is only accurate to approximately 15' (5 meters), so you could have actually traveled 73' up to 103'. So, after 60 seconds your traveled distance could be off as much as 900', which is a 17% variation.

Every reading that the gps takes could be 15' north, south, east, or west of the actual location. In effect, the gps could have you zig zagging down the highway and traveling much further than you actually traveled.

However, what I have stated above is not an accurate description of the process by which the gps calculates speed. I have done exhaustive testing on speed and distance using known benchmarks and the odometer and speedometer readings are dead on.

It's true that there is a lag time so that if you are accelerating or decelerating then your speed is not displayed in real time. But, holding a steady speed for as little as one second will deliver an accurate count.

I do not know or understand the speed calculation process for gps devices. I only know them to be accurate as a result of many miles and hours of comparison. I have had three different brands of gps devices running at one time in my auto and they were all reading precisely the same speed and distance over hundreds of miles.

I don't understand it but I believe it. :D
 

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Dumb question but does going up or down a hill change GPS speed if the M/C tires are turning the same RPMs in both tests????
 

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Rastoff said:
... you shouldn't rely on the GPS to indicate speed unless you are traveling at a steady rate.
poooey on the rest ... this last sentence is where the meat is ...

if/when traveling "steady state" the GPS is VERY accurate regarding its ability to calculate mph.
65mph down the interstate qualifies as "steady state".

Those plus or minus 5 meters accuracy you read is with reference to taking a fix one place and then moving several 10's or 100's of miles to another place ... when traveling steady state, even if the GPS is "off" by 10 or 15 feet it is CONSISTENTLY off by that same 10 or 15 feet from 1 second to the next and thus those small deviations become null.
From 1 second to the next the GPS is VERY good at knowing where it was and now where it is and thus very good at being able to calculate mph.

The GPS I tested on the bike is one of three that I have in my airplane.
In the airplane all 3 gps's are within 1 mph of each other and those three are within 2mph of the antiquated but still very accurate Loran that I still have for backup.

Apply the same argument to the analog speedo
... get going about 130mph and then run into a brick wall
... I bet the analog speedo will take some "time" to return to zero
... although it might never return to zero since it will be plastered to the inside of the case :)

I'll bet anyone $100 my GPS is more accurate than the wing analog speedo.

Dennis
 
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