Three questions

[nojyttap]

1. How accurate is the speed on my 910? It appears to be about 4 mph slow up to about 25 or 30 mph, then about 3 mph slow up to around 75-80, and 2 mph slow after that...I know what you're think but my car won' go fast enough to make them match.

2. Why are some roads along my route not displayed? Although I bought my TT for business travel I use it when commuting into work. I've noticed that when I'm on the toll road some roads, even ones with ramps are not displayed and other roads, that don't have access to the toll road are displayed. I haven't tried just driving off onto one of the undisplayed ramps to see what happens...I'm afraid of driving off into the twilight zone that my TT can't decribe.

3. Is there a way to zoom out the view and keep it there? When I'm on the toll road and out in the country there isn't much displayed on the screen, see #2. I'd like to be able to zoom out and stay there to show what's further ahead.

Thank you for your attention.

BTW I just added the auto shutoff feature and it works great!

 

[Pedro2NR]

Hello,

1) Yes it is accurate. Speedometer on vechiles aren't accurate to assure saftey etc.

2) This is a map error. What version map does your 910 have?

3) So far I've only seen this feature on the x20 series. I have downloaded the Navcore 7 lite firmwire for my 910 and didn't see this feature.

 

[46jimbo]

3. Switching to 2D view allows you to see a bit more real estate. But you still can't adjust the zoom.

 

[nojyttap]

My map version is 650.

As I said I have not tried taking an off ramp that is not shown. I assumed that the software just didn't show them because they aren't part of the route and if I turned off on one that it would add it and try to update my route. I will test this later today.

 

[The Spook]

1) Yes it is accurate. Speedometer on vechiles aren't accurate to assure saftey etc.

As Pedro says, your TT is accurate (very accurate), it is your speedo that is not.

However, the speedo over-reading has nothing to do with safety. All manufacturers do this to absolve themselves of any liability claims relating to speeding offences. You can never claim that "...my speedo said I was doing 29mph! (and it must therefore be Ford's fault, not mine)" when ticketed at 34mph. If you get clocked at 34mph, your speedo would have indicated you were doing at least 37mph.

Speedo's typically over-read by approximately 10%. In many countries legislation permits speedo's to over-read by 10%, nowhere does legislation permit them to under-read, by any amount. Hence, most manufacturers go for as close to 10% as they can get. Every speedo over-reads.

 

[2extreme983]

Every speedo over-reads.

Not true. Police vehicles (Crown Vic's, etc) speedo's (as you say) are 100% accurate and certified. This is for when one "paces" your speed so that it holds up in court if needed.

I know this had nothing to do with this thread but just thought I'd clarify that!

 

[The Spook]

Not true. Police vehicles (Crown Vic's, etc) speedo's (as you say) are 100% accurate and certified.

You are quite right, I should have mentioned this exception. I didn't because it didn't seem relevant to the OP's question, or to the average person. My bad!

Of course, police vehicles are not delivered with accurate speedo's, they have to be re-calibrated specially. They require regular re-calibration and certification in order to be admissable in court.

What's a 'Crown Vic'?

 

[2extreme983]

You are quite right, I should have mentioned this exception. I didn't because it didn't seem relevant to the OP's question, or to the average person. My bad!

Of course, police vehicles are not delivered with accurate speedo's, they have to be re-calibrated specially. They require regular re-calibration and certification in order to be admissable in court.

What's a 'Crown Vic'?

I know it wasn't relevant and sorry for jacking the thread .

A Crown Vic = Crown Victoria (Police Interceptor) made by Ford. These most common police vehicles do get delivered with accurate speedo's from the factory. The speed gauge actually says the words "Certified Calibration". I do agree that they need to get re-calibrated over time, but they are certified as accurate!

 

[jimj]

The speed reading in my 07 Rainier matches my 910 all the time.

 

[Bwanap]

My Mazda 3 reads 1 mph over TT at all times.

 

[Locotuss]

okay, jumping in on this one, first- Police vehicles do have Certified Speedo's, most speedo are pretty accurate, but most dealers or owners change recommended specs and with larger tires it changes the speedo's.

Most Police do not rely on the speedometers for a pace, as most speedo's only have 5 mph markings. Police use the moving mode of the radar unit to verify accurate speed readings, that why in court the speed could be 78 in a 60 zone, with a speedo only you could only round down to give benefit of the doubt.

As far as accurate for the tomtom, only when the speed is steady, it is right on accurate, accelerating quickly or decelerating quickly will stair step the speed
.