Speedo Accuracy in Videos - is 204 mph really 204 mph?

FullTilt

New Member
Nov 3, 2008
13
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0
N. Vancouver BC
http://ca.youtube.com/watch?v=IcKcCy7aodA

For a long time, I've wanted to show a video where the speedo and a GPS are framed together that shows the GPS unit sweeping past 200mph.

The old superkaos video showing his freeway blast where the speedo sweeps to 220+, but SK himself said it was wildly off in terms of accuracy but has been seen untold millions of times and hyped because of what it shows.

This is an Anderson Turbo equipped bike (very cool owner/rider BTW) with a stock wheelbase that just flys.

It might not be Noonan-esque, but it is still pretty cool.
 

albo_bizak

New Member
Jul 28, 2007
51
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Cleveland
I was driving with my friend in his slow ass Dodge Stealth and he has his TOM TOM on when we were doing 85mph it would show 78mph. We thought there was something wrong with the car and we tried it on a slower car a honda civic, will same exact thing happend too. They are just good to take from point A to point B and they suck at measuring how fast you going.
 

pparrigo

India Delta OneZero Tango
Feb 12, 2008
115
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WNY
Christ those are fast...

Unfortunately I agree with those above me. The speedometer in my Mk3 is off by 5-7mph in the 70-80mph range according to my retarded TomTom (Garmins are better if you happen to be in the market, btw). Its partly a liability thing on the manufacturer's end. If the speedo reports you driving faster, you end up driving a little slower.

Also, part of the discrepancy lies in the way the speed is calculated on each. In-car GPS' don't always account for elevation, most of them are level speeds (i.e. you could be doing a true 70mph up a hill, but the GPS will show 67mph as you are covering less horizontal distance in the same amount of time).
 

Poodles

I play with fire
Jul 22, 2006
16,757
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Fort Worth, TX
GPS's work off triangulation, if they have 4 satellites they can calculate altitude as well.

I love my TomTom for the price, it shows my speedo as being 5MPH fast everywhere, even at speeds over 100MPH.

Most motorcycle speedos are optimistic, maybe the busa is the exception? Even the digital ones are reportedly optimistic.
 

shenronzero

spitfire
Oct 19, 2007
407
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orlando/ New Smyrna Beach FL
Poodles;1178911 said:
GPS's work off triangulation, if they have 4 satellites they can calculate altitude as well.

I love my TomTom for the price, it shows my speedo as being 5MPH fast everywhere, even at speeds over 100MPH.

Most motorcycle speedos are optimistic, maybe the busa is the exception? Even the digital ones are reportedly optimistic.

i have to keep my GPS charged and in my car because i did a auto to R154 and my speedo at highway speed is around 10mph off... i know mine works because i got in a brand new car with the gps and ran by a radar that shows you how fast your going... all 3 were the same... oh garmin c330.. walmart:biglaugh:
 

Boost Lee

Bee Doo Bee Doo Bee Doo
Staff member
Sep 13, 2006
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Indianapolis, IN
Please take this into consideration coming from a guy that used to demo and sell Navigational GPS units.

ALL modern day and most high end GPS units (Yes, even a TomTom although I despise most of them...Garmin all the way),
All are sighted in with at least 4 satellites.

As mentioned, According to the unit, can and will tell you your altitude as well.
They are accurate to say the least.

Unfortunately albo_bizak, I'm going to have to side with your friends TomTom over the "slow ass Dodge Stealth's" "old ass speedometer". ;)

Supra shows 130MPH on the speedometer - Garmin shows 119-120MPH.

Mind shock, I know. :)

Jeff
 

Poodles

I play with fire
Jul 22, 2006
16,757
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Fort Worth, TX
I've also verified my tomtom with the radar signs on the side of the road, it's far more accurate than the stock speedo...if a bit slower ;)

My tom tom is currently tracking 11 satellites, so I trust the accuracy. Normal display doens't show altitude, but there is an app to do it...
 

Boost Lee

Bee Doo Bee Doo Bee Doo
Staff member
Sep 13, 2006
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Indianapolis, IN
An app? To hell with all that.

I just press my "Gauges" button and it pulls up ALL of that information with the poke of a finger.
(ie. Max speed/Average speed/Time stopped/Time moving/Altitude/Mileage used/Odometer, etc).

hehe. ;)

Jeff
 

honestabe

Happy as hell :D
Jan 15, 2006
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Mount Vernon, WA, USA
www.cardomain.com
The last 4 times I've been pulled over by cops the officer quoted the exact speed my GPS showed, not my guage cluster speedo speed. This was with bot a Garmin (don't remember the model since it was stolen) and more recently my Tom Tom One 3rd Edition. I trust my Tom Tom's speedo before I trust the factory one.


Adam