Speedo OFF?

Batman229 · 11-02-2004, 09:25 PM

I was stopped at a red light today and a cop pulled up next to me. Of course I let him hit the gas and pull away, but he was driving very slowly. I had to get to a class so I wasnt about to drive behind him. I set the cruise control to 55 and slowly I passed him. Once I was about a cars length away he pulls up next to me and I didnt turn to look untill he blipped his sirens. He pointed to his speedo, then to me, then pointed behind him. I knew he ment slow down but I was only doing 55 in a 55. SO I slowed down to around 40, pulled behind him and kept his pace. Could my speedo be off between 5-10 mph? Or was he just messing with me?

Tom Roper · 11-02-2004, 09:29 PM

He was messing with you mostly. My Garmin GPS says my Titan speedometer reads LOW by about 1.5-2.0 mph at an indicated 60. That's unusual, since usually the error is the other way on other vehicles I've owned at least. Figure you might have been going 56.0-56.5 when he messed with you.

Titan Kid · 11-02-2004, 09:31 PM

if you were going to "class" I imagine your fairly young, so he probably was just messing with you. A young kid in a brand new $30K truck would be the type of person for him to mess with. I am only 19 and a couple of weeks ago I got pulled over because my temp tags looked suspicious. WTF...

Finnattic · 11-02-2004, 09:34 PM

Quote:

Originally Posted by Batman229

I was stopped at a red light today and a cop pulled up next to me. Of course I let him hit the gas and pull away, but he was driving very slowly. I had to get to a class so I wasnt about to drive behind him. I set the cruise control to 55 and slowly I passed him. Once I was about a cars length away he pulls up next to me and I didnt turn to look untill he blipped his sirens. He pointed to his speedo, then to me, then pointed behind him. I knew he ment slow down but I was only doing 55 in a 55. SO I slowed down to around 40, pulled behind him and kept his pace. Could my speedo be off between 5-10 mph? Or was he just messing with me?

I've heard of others complaining about this. To be off by that much though. Even if speed limit was 55 and you set it for 55 and your off by 5 usually they'll give you 5 or so over without messing w/ you. Are you sure you were in a 55, almost sounds like you were in a 45.

Have a buddy or two to be sure their's isn't off too pace you at a given speed to see what the difference is. He very well coulda been screwing w/ you...

TYTAIN · 11-02-2004, 09:36 PM

Should have pulled in behind him and gave him a Dale Earnhardt as he went into the corner.

Finnattic · 11-02-2004, 09:42 PM

Quote:

Originally Posted by TYTAIN

Should have pulled in behind him and gave him a Dale Earnhardt as he went into the corner.

Dale "Pit Maneuver" Earnhardt

A little known "urban legend" the pit maneuver was invented by ole Big E and adopted by the police.

Ayrow · 11-03-2004, 03:07 AM

My Garmin GPS shows my speedo as being almost perfectly right-on.

dynamohm · 11-03-2004, 03:58 AM

My speedo is right I got a ticket for 69 in a 55 when I saw the cop with his radar I looked at the speedo and I was going 68. I have noticed though that my odometer is off by about 5%. If I use the mile markers on the side of most interstates I count 10 miles off, yet my odometer reads 91/2.

rarjar · 11-03-2004, 05:42 AM

Quote:

Originally Posted by dynamohm

My speedo is right I got a ticket for 69 in a 55 when I saw the cop with his radar I looked at the speedo and I was going 68. I have noticed though that my odometer is off by about 5%. If I use the mile markers on the side of most interstates I count 10 miles off, yet my odometer reads 91/2.

Sounds like it's time for a good radar detector!!!

"Knock on wood," I've used one now for almost 15 years and got one ticket (my fault as I ignored the warning). Several good ones out there-- I have owned the cheap ones (e.g, Whistler) and the expensive ones by Escort (used to be Cincinnati Microwave) and have found the Bel 980 to be the best I've had. My thoughts.

TYTAIN · 11-03-2004, 05:56 AM

Quote:

Originally Posted by Finnattic

I've heard of others complaining about this. To be off by that much though. Even if speed limit was 55 and you set it for 55 and your off by 5 usually they'll give you 5 or so over without messing w/ you. Are you sure you were in a 55, almost sounds like you were in a 45.

Have a buddy or two to be sure their's isn't off too pace you at a given speed to see what the difference is. He very well coulda been screwing w/ you...

Cool Avatar, where did you get it?

Dude · 11-03-2004, 06:10 AM

We have those radar stations set up from time to time in my City that clock everyone driving by and gives a readout in big numbers. My vehicles have all been approx. 2 miles under what the radar says, i.e., when the radar says I am going 45mph my speedo says 43. This seems a little too coincidental. I think this is common place as the manufacturers probably make sure that the speedo never causes you to get a ticket due to it saying you are going slower than you really are. Sort of like the game they play with the fuel gauges. They always make you think you have less fuel than you really do.

TriKKy · 11-03-2004, 07:10 AM

This ties into what I've been saying all along. If the odo is off by ~8% for me, it would be reasonable that the speedo is of too. I have done a few calculations, and based just on the circumference difference between the XE and a truck with OR there is something like a 6.7%error/mile if the truck hasn't been calibrated for the difference.

Now, if you translate the 6.7% error into the 55mph reading...58.685mph is what you get. If it seems to be more, like it is with mine, then it would be even higher.

RS250R · 11-03-2004, 08:48 AM

my speedo is off by about 2 as well. indicates low....

vector6 · 11-03-2004, 10:16 AM

my speedo is spot on with my Magellan ..