09-18-2013, 07:54 PM
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#11 (permalink)
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Master EcoModder
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I just check the odo readings on my normal weekday trip which is 39.8 miles round trip. This is a camparison of probably every vehicle average in my garage, something like 16 different vehicles.
The truck reads low since I put larger tires on it, so I correct it by 1.026 to get the true distance.
Occasionally they put one of those radar machines on the side of the road and I'll check the speedometer against the radar. The truck and Fiesta are spot on, need to check the bikes, since they are supposed to be optomistic.
regards
Mech
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09-18-2013, 07:57 PM
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#12 (permalink)
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Cyborg ECU
Join Date: Mar 2011
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My car currently understates miles by about 5.5%... checked it repeatedly with a GPS unit and ridewithgps.com
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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09-19-2013, 12:11 PM
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#13 (permalink)
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Hypermiler
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My old Civic was almost exactly right with new tires. With worn tires it overreported by about 2%. My Fit underreports by a little.
My 2004 Odyssey is one of the ones in the class-action lawsuit. It DOES overreport by about 5%.
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11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
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09-19-2013, 02:53 PM
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#14 (permalink)
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Quote:
Originally Posted by euromodder
1% is 1% 
I'd add it.  |
The difference between new tires and worn tires is approximately 2% (new is typically 10/32" tread depth, 2/32" is worn = 8/32" difference. Times two for tread on top and bottom is 1/2" on a 26" tire for 2%). Do you factor that in as well? |
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The Following User Says Thank You to darcane For This Useful Post:
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09-19-2013, 03:00 PM
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#15 (permalink)
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Join Date: Aug 2009
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Quote:
Originally Posted by Old Mechanic
Occasionally they put one of those radar machines on the side of the road and I'll check the speedometer against the radar. The truck and Fiesta are spot on, need to check the bikes, since they are supposed to be optomistic.
regards
Mech
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I've seen a wide range on my motorcycles. The worst in my Kawasaki 650R, the odometer reads very close (within 1%) but my speed reports 10% higher than actual! (checked using GPS, radar machines, and odometer check points). Most of my bikes have been 3-5% off on the speedo with the odometer being far more accurate. |
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09-19-2013, 09:16 PM
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#16 (permalink)
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Master EcoModder
Join Date: Mar 2009
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Oh good, i thought there was something wrong with my brand new car's digital odometer.
Odo seems to be underreporting by 3% when compared to my gps.
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09-20-2013, 08:54 PM
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#17 (permalink)
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Exceptional Member
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Another thought, does a GPS take grades into account when you use it for distance measurement?
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Don't know why it says 00, it's a 95
374,000 miles and tired.
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09-20-2013, 10:53 PM
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#18 (permalink)
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Cyborg ECU
Join Date: Mar 2011
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Quote:
Originally Posted by Lbar
Another thought, does a GPS take grades into account when you use it for distance measurement?
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Yes.
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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