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I took my '99 on what I thought was a 167 mile ride to check out my new, to me, seat (thanks Byron). After downloading the tracks to Garmin RoadTrip, the mileage was only 152. I knew the speedometer was off 10%, but didn't think the odometer was too. Are the two related?

Jer
 

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They should be independent I'd think. Even my Suzuki had an "optimistic" speedometer but the odometer was spot on.

EDIT: But now that I recall, the speedo on the Zuki was a needle but the odometer was digital. Different from the dial odemeter you and I have on our LT.
 

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Most motorcycle speedometers will not have the same error as a percentage between the speed and odometer. Normally it seems the odometer is the information that the manufacturers seem to target for accuracy and the speedometer reading is just close enough. Strange as it may seem Harley's are pretty good at getting both very close but most others including my LT read 4 to 5 MPH fast at highway speeds. I've checked my odometer over a 100 mile leg against my GPS and it was within 2/10ths of a mile. I'd call that damn near perfect. It kinda bugs me that after spending so much money on a new bike it didn't even come with an accurate speedometer. Of course 20 MPH increments on the face doesn't lend itself to an accurate quick scan of your speed either. It's gotten to the point I really don't even look at the speedometer anymore. I just instinctively look at my trusty over priced NAV III unit. :) Boy I feel better now!
 

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Hello jers99lt

The speed indicator is a rate display where the odometer is the display of a measurement calculation .
When comparing GPS distances to vehicle readout the distances will be the most accurate during a straight a course , the faster and longer you drive winding roads the more different the distances calculated will be . It has something to do with the sampling , calculating rate of the GPS . The new high end ones tend to be faster . If you want to see a Garmin nuvi loose it's mind and lock up take one on a commercial jet and have find a route . It just was not programed for that speed and not on a road it could find .

Bob G
 

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Discussion Starter #5
gbob said:
Hello jers99lt

The speed indicator is a rate display where the odometer is the display of a measurement calculation .
When comparing GPS distances to vehicle readout the distances will be the most accurate during a straight a course , the faster and longer you drive winding roads the more different the distances calculated will be . It has something to do with the sampling , calculating rate of the GPS . The new high end ones tend to be faster . If you want to see a Garmin nuvi loose it's mind and lock up take one on a commercial jet and have find a route . It just was not programed for that speed and not on a road it could find .

Bob G
Thanks, that makes complete sense to me now. The samplings are point-to-point distances. I was riding the twistiest roads I could find through the corn/soy fields of northern IL. Not many!, It hit me as odd that both the speedo and odo were the same 10% off, and I couldn't resolve the correlation between the two.
Long story short, there is no correlation. Thanks for all the input.

Jer
 

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The LTs odo (pre-05 - don't know whether they changed anything other than digi display) were about 3% optimistic IIRC
 
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