Accurate way to measure route distance

[oldtamiyaphile]

Originally Posted by Cobb

You spent about 600 more than I did for my refurbished one with lifetime maps n traffic from ebay. I never paid attention to the miles as I assume the margin of error was enough to screw up any sense of accuracy. Plus I take detours for traffic reasons, days I only feel like making right turns, days I feel someone is following me, days I want fast food or inconvenience items, etc.

Yeah, but it's accurate to about 1 meter and I can actually see my line through corners when I play a trip/lap back on the PC. It also logs points at an adjustable rate so I can compare and record performance from one day/lap/trip to the next. Makes accurate coast down tests very easy and logs speed down to 0.1km/h with time stamps.

I find my daily use Garmin to be very accurate and repeatable, but cheaper units without standby will usually be short a few miles as the GPS boots up with the car already underway. The better units have a standby feature so they're ready to go at key on.

[Cobb]

I got a tomtom. It was ok at first, but the recent updates it takes a good 30 seconds to power up, then another 30 to find the gps signal. Its rather slow now responding to the screen touches. It was quick at first.

I had a garmin street pilot c330. It was good at getting me lost. My tomtom, I use its POI menu to find restaurants and places to eat where I live or work.

[D.O.G.]

Originally Posted by Old Mechanic

Does this mean GPS readings do not show elevation changes that would affect distance travelled, something I had wondered about.

regards
Mech

OK, I compared my GPS (Tom Tom) and ridewithGPS's figures.

The GPS shows 51.9 km to work (it doesn't give the elevation change), ridewithGPS shows 52.2 km with 592 m overall elevation change.

I really don't know which is more accurate for distance.

[Cobb]

Interesting..... Thanks for checking that.