speedometer not properly calibrated

How can you check if the speedometer is not properly calibrated and if I ask
a mechanic to do it how much should it cost?

Thanks,
W

sh-aly, 11/29/2005,5:42:19 AM, wrote:
[color=blue]
> How can you check if the speedometer is not properly calibrated[/color]

1) Drive by a state trooper quickly and he'll let you know what he
considers your proper speed to be!
2) Borrow someone's portable GPS system and it should tell you the
proper speed.
3) Drive the speed limit and you won't have anything to worry about.

In my experience, every car I've owned seemed to have a speedometer
that showed 2-4 MPH below actual speed.
--
"Golf is like an 18-year-old girl with big boobs. You know it's wrong
but you can't keep away from her." -- Val Doonican

> How can you check if the speedometer is not properly calibrated and if I[color=blue]
> ask a mechanic to do it how much should it cost?[/color]

If you belong to the Auto Club, they have a roving speedometer check
vehicle. They post its location in their magazine, which is usually at one
of their local offices. I believe it is a free check.

The GPS idea is also good.

B~

"sh-aly" <wqadeer@stanford.edu> wrote in message
news:dmhbac$g7g$1@news.Stanford.EDU...[color=blue]
> How can you check if the speedometer is not properly calibrated and if I
> ask a mechanic to do it how much should it cost?
>
> Thanks,
> W
>[/color]
I checked my Tundra against a GPS unit and the Tundra was 2 mph fast at 60
mph, but only 1 mph fast at 30. Not enough to worry about.

"sh-aly" <wqadeer@stanford.edu> wrote in message
news:dmhbac$g7g$1@news.Stanford.EDU...[color=blue]
> How can you check if the speedometer is not properly calibrated and if I
> ask a mechanic to do it how much should it cost?
>
> Thanks,
> W[/color]

Besides the GPS idea that badgolferman posted and the auto club speedometer
check that b.peg posted, you can try driving at 60 MPH and watching the mile
markers. You should do this over at least a 10 mile stretch to average
things out.

Besides asking someone with a speed measuring gun to measure your speed, the
only way to check for sure is with a chassis dynamometer. These are very
expensive machines and not many shops have them.
--
Ray O
correct the return address punctuation to reply

"B. Peg" <bent_peg@worldnet.att.net> wrote:
[color=blue][color=green]
>> How can you check if the speedometer is not properly calibrated and if I
>> ask a mechanic to do it how much should it cost?[/color]
>
>If you belong to the Auto Club, they have a roving speedometer check
>vehicle. They post its location in their magazine, which is usually at one
>of their local offices. I believe it is a free check.
>
>The GPS idea is also good.
>
>B~
>[/color]

But how accurate is the GPS?...I have a Magellan Meridan
Gold...not very expensive (or is expense a factor?)
--

-Gord.
(use gordon in email)

"Gord Beaman" <gord@islandtelecom.com> wrote in message
news:jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com...[color=blue]
> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>[color=green][color=darkred]
>>> How can you check if the speedometer is not properly calibrated and if I
>>> ask a mechanic to do it how much should it cost?[/color]
>>
>>If you belong to the Auto Club, they have a roving speedometer check
>>vehicle. They post its location in their magazine, which is usually at
>>one
>>of their local offices. I believe it is a free check.
>>
>>The GPS idea is also good.
>>
>>B~
>>[/color]
>
> But how accurate is the GPS?...I have a Magellan Meridan
> Gold...not very expensive (or is expense a factor?)
> --
>
> -Gord.
> (use gordon in email)[/color]

If the GPS is WAAS enabled, then it is probably accurate to within 10 or 12
feet. Without WAAS, it is probably within 30 feet.

--
Ray O
correct the return address punctuation to reply

On Tue, 29 Nov 2005 02:42:19 -0800, sh-aly wrote:
[color=blue]
> How can you check if the speedometer is not properly calibrated and if I ask
> a mechanic to do it how much should it cost?
>
> Thanks,
> W[/color]

Um, drive 110MPH in a 50MPH zone?

They'l let you know!

Seriously what I do is look for one of those radar signs they put out once
in a while. My speedos are all within 5% of what they say, even after
monkeying with tire sizes.

Or, just go down to the PD and ask them to clock you! They will.

--
I've spent a great deal of money on Whiskey, Women and Fast Cars

The rest I've squandered.

In article <jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com>,
Gord Beaman <gord@islandtelecom.com> wrote:
[color=blue]
> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>[color=green][color=darkred]
> >> How can you check if the speedometer is not properly calibrated and if I
> >> ask a mechanic to do it how much should it cost?[/color]
> >
> >If you belong to the Auto Club, they have a roving speedometer check
> >vehicle. They post its location in their magazine, which is usually at one
> >of their local offices. I believe it is a free check.
> >
> >The GPS idea is also good.
> >
> >B~
> >[/color]
>
> But how accurate is the GPS?...I have a Magellan Meridan
> Gold...not very expensive (or is expense a factor?)[/color]

I have the cheapest GPS unit around, but even it is very accurate. I
used to do the 'drive 60 and check the mile markers" method, but GPS has
replaced it.

"Ray O" <rokigawa@tristarassociatesDOT.com> wrote:
[color=blue]
>
>"Gord Beaman" <gord@islandtelecom.com> wrote in message
>news:jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com...[color=green]
>> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>>[color=darkred]
>>>> How can you check if the speedometer is not properly calibrated and if I
>>>> ask a mechanic to do it how much should it cost?
>>>
>>>If you belong to the Auto Club, they have a roving speedometer check
>>>vehicle. They post its location in their magazine, which is usually at
>>>one
>>>of their local offices. I believe it is a free check.
>>>
>>>The GPS idea is also good.
>>>
>>>B~
>>>[/color]
>>
>> But how accurate is the GPS?...I have a Magellan Meridan
>> Gold...not very expensive (or is expense a factor?)
>> --
>>
>> -Gord.
>> (use gordon in email)[/color]
>
>If the GPS is WAAS enabled, then it is probably accurate to within 10 or 12
>feet. Without WAAS, it is probably within 30 feet.[/color]

It claims to be, and it claims 'accurate to within 3 meters' so
perhaps it it...but that means the 'speed' is accurate does
it?...(Yes I suppose it does) :)
--

-Gord.
(use gordon in email)

Sean Elkins <sean_elkins@yahoo.com> wrote:
[color=blue]
>In article <jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com>,
> Gord Beaman <gord@islandtelecom.com> wrote:
>[color=green]
>> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>>[color=darkred]
>> >> How can you check if the speedometer is not properly calibrated and if I
>> >> ask a mechanic to do it how much should it cost?
>> >
>> >If you belong to the Auto Club, they have a roving speedometer check
>> >vehicle. They post its location in their magazine, which is usually at one
>> >of their local offices. I believe it is a free check.
>> >
>> >The GPS idea is also good.
>> >
>> >B~
>> >[/color]
>>
>> But how accurate is the GPS?...I have a Magellan Meridan
>> Gold...not very expensive (or is expense a factor?)[/color]
>
>I have the cheapest GPS unit around, but even it is very accurate. I
>used to do the 'drive 60 and check the mile markers" method, but GPS has
>replaced it.[/color]

Thanks...this one was just under 500 about six months ago...lots
of fun...
--

-Gord.
(use gordon in email)

On Wed, 30 Nov 2005 02:06:11 +0000, Gord Beaman wrote:
[color=blue]
> Sean Elkins <sean_elkins@yahoo.com> wrote:
>[color=green]
>>In article <jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com>,
>> Gord Beaman <gord@islandtelecom.com> wrote:
>>[color=darkred]
>>> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>>>
>>> >> How can you check if the speedometer is not properly calibrated and if I
>>> >> ask a mechanic to do it how much should it cost?
>>> >
>>> >If you belong to the Auto Club, they have a roving speedometer check
>>> >vehicle. They post its location in their magazine, which is usually at one
>>> >of their local offices. I believe it is a free check.
>>> >
>>> >The GPS idea is also good.
>>> >
>>> >B~
>>> >
>>>
>>> But how accurate is the GPS?...I have a Magellan Meridan
>>> Gold...not very expensive (or is expense a factor?)[/color]
>>
>>I have the cheapest GPS unit around, but even it is very accurate. I
>>used to do the 'drive 60 and check the mile markers" method, but GPS has
>>replaced it.[/color]
>
> Thanks...this one was just under 500 about six months ago...lots
> of fun...[/color]

I don't get lost enough to spend $500!!!

I know my way EVERYWHERE! (or so it seems...)

--
I've spent a great deal of money on Whiskey, Women and Fast Cars

The rest I've squandered.

"Gord Beaman" <gord@islandtelecom.com> wrote in message
news:i459r1td0m9e5kkv6b67h4go9bh9kb1lve@4ax.com...[color=blue]
> "Ray O" <rokigawa@tristarassociatesDOT.com> wrote:
>[color=green]
>>
>>"Gord Beaman" <gord@islandtelecom.com> wrote in message
>>news:jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com...[color=darkred]
>>> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>>>
>>>>> How can you check if the speedometer is not properly calibrated and if
>>>>> I
>>>>> ask a mechanic to do it how much should it cost?
>>>>
>>>>If you belong to the Auto Club, they have a roving speedometer check
>>>>vehicle. They post its location in their magazine, which is usually at
>>>>one
>>>>of their local offices. I believe it is a free check.
>>>>
>>>>The GPS idea is also good.
>>>>
>>>>B~
>>>>
>>>"
>>> But how accurate is the GPS?...I have a Magellan Meridan
>>> Gold...not very expensive (or is expense a factor?)
>>> --
>>>
>>> -Gord.
>>> (use gordon in email)[/color]
>>
>>If the GPS is WAAS enabled, then it is probably accurate to within 10 or
>>12
>>feet. Without WAAS, it is probably within 30 feet.[/color]
>
> It claims to be, and it claims 'accurate to within 3 meters' so
> perhaps it it...but that means the 'speed' is accurate does
> it?...(Yes I suppose it does) :)
> --
>
> -Gord.
> (use gordon in email)[/color]

"Accurate to within 3 meters" is about 9 or 10 feet. I assume that the
clock function on the GPS is also pretty accurate so the distance/speed
equation should be pretty accurate.
--
Ray O
correct the return address punctuation to reply

"Ray O" <rokigawa@tristarassociatesDOT.com> wrote in message
news:c4279$438cd248$44a4a10d$20195@msgid.meganewsservers.com...[color=blue]
>
> "Gord Beaman" <gord@islandtelecom.com> wrote in message
> news:jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com...[color=green]
> > "B. Peg" <bent_peg@worldnet.att.net> wrote:
> >[color=darkred]
> >>> How can you check if the speedometer is not properly calibrated and if[/color][/color][/color]
I[color=blue][color=green][color=darkred]
> >>> ask a mechanic to do it how much should it cost?
> >>
> >>If you belong to the Auto Club, they have a roving speedometer check
> >>vehicle. They post its location in their magazine, which is usually at
> >>one
> >>of their local offices. I believe it is a free check.
> >>
> >>The GPS idea is also good.
> >>
> >>B~
> >>[/color]
> >
> > But how accurate is the GPS?...I have a Magellan Meridan
> > Gold...not very expensive (or is expense a factor?)
> > --
> >
> > -Gord.
> > (use gordon in email)[/color]
>
> If the GPS is WAAS enabled, then it is probably accurate to within 10 or[/color]
12[color=blue]
> feet. Without WAAS, it is probably within 30 feet.
>
> --
> Ray O
> correct the return address punctuation to reply[/color]

Except he needs the accuracy measuring the speed, which isn't done by
evaluating the difference between positions, at least not typically:

[url]http://gpsinformation.net/main/gpsspeed.htm[/url]

As noted on the link, Garmin (a popular manufacturer, I have one of their
units) claims .1 mph accuracy. This probably depends on pretty good skyview
and satellite selection. On a highway in a fairly level rural location,
with no obstructions and the GPS placed where it can easily see the sky (or
at least the satellites currently in the sky), you'll get that accuracy. I
have a Sienna. If I put the GPS towards the front of the dash, it gets a
pretty good skyview. If it's reporting good positional accuracy, speed
measurement will probably be pretty accurate, too.

Got no money? Set your cruise to 60 mph and time mile markers over a
straight-ish 10 mile stretch of road. A stopwatch and I-80 in Nebraska are
handy for this.

Got $100 and an interest in radio, electronics, hunting, fishing, camping or
hiking? Get a cheap GPS and check your speed that way (have a passenger
actually work the GPS) and the GPS will provide entertainment later on. You
can use them in aircraft (after the pilot says electronics are OK - just
hold it up to the window), boats, woods, etc.

Got lotsa money? Get a mapping or navigating GPS unit.

To be sure you're using it right, check gpsinformation.net for more info and
be sure to read your product manual. GPS is not magic (it just seems that
way) and it does have its limitations. Look over gpsinformation.net BEFORE
you buy.

YMMV.

On Tue, 29 Nov 2005 23:25:25 -0600, "Ray O"
<rokigawa@tristarassociatesDOT.com> wrote:
[color=blue]
>"Gord Beaman" <gord@islandtelecom.com> wrote in message
>news:i459r1td0m9e5kkv6b67h4go9bh9kb1lve@4ax.com...[color=green]
>> "Ray O" <rokigawa@tristarassociatesDOT.com> wrote:
>>[color=darkred]
>>>
>>>"Gord Beaman" <gord@islandtelecom.com> wrote in message
>>>news:jdk8r1dvp0fho2m04ejsnskugaaa827uj8@4ax.com...
>>>> "B. Peg" <bent_peg@worldnet.att.net> wrote:
>>>>
>>>>>> How can you check if the speedometer is not properly calibrated and if
>>>>>> I
>>>>>> ask a mechanic to do it how much should it cost?
>>>>>
>>>>>If you belong to the Auto Club, they have a roving speedometer check
>>>>>vehicle. They post its location in their magazine, which is usually at
>>>>>one
>>>>>of their local offices. I believe it is a free check.
>>>>>
>>>>>The GPS idea is also good.
>>>>>
>>>>>B~
>>>>>
>>>>"
>>>> But how accurate is the GPS?...I have a Magellan Meridan
>>>> Gold...not very expensive (or is expense a factor?)
>>>> --
>>>>
>>>> -Gord.
>>>> (use gordon in email)
>>>
>>>If the GPS is WAAS enabled, then it is probably accurate to within 10 or
>>>12
>>>feet. Without WAAS, it is probably within 30 feet.[/color]
>>
>> It claims to be, and it claims 'accurate to within 3 meters' so
>> perhaps it it...but that means the 'speed' is accurate does
>> it?...(Yes I suppose it does) :)
>> --
>>
>> -Gord.
>> (use gordon in email)[/color]
>
>"Accurate to within 3 meters" is about 9 or 10 feet. I assume that the
>clock function on the GPS is also pretty accurate so the distance/speed
>equation should be pretty accurate.[/color]

It is good enough to put a cruise missile thru a window....that is
good enough for me...LOL

--

Scott in Florida