Does Rever use GPS or the cell network to log where you've travelled? If it does, then unlike some dedicated GPS units (with inertial nav built in that allow the system to accurately plot your position several times a second & accurately measure the distance between those spots) and your Spyder's trip meter that records every rotation of the tire, the Rever trip log is likely to skip the distance between spots where it's lost signal for a bit. It doesn't take much signal loss to make a difference in distance travelled, you might not even notice the little gaps happening, but when they happen fairly often as you ride, the cumulative distance lost can add up to A LOT!! :shocked: The other side of that is that if you spend a lot of time spinning your rear tire, then that spinning can add a few supposed miles of travel to your trip meter that is actually just wheelspin & not distance travelled at all! But that probably won't be quite as much as 30 miles out of 172 unless you spent a whole HEAP of time with the rear tire all lit up! :lecturef_smilie:
We are fairly lucky here in Aus, in that most of our biiiig distances are out in wiiide open spaces, so this sorta thing isn't often a problem with the lesser GPS units when travelling between cities or in the Outback, those units will still get some signal pretty much everywhere out there; and even if there's vast distances & areas where there's no cell coverage, it doesn't take a massively high tower to ensure that what cell signal there is canbe useful for miles over the unobstructed flat plains around those towers!! But in our High Country & the Snowy Mountains, where there's heaps of ups & downs, deep valleys, lotsa tree & scrub coverage, & really winding roads with deep cuttings & overhangs where the clear 'line of sight' to get signal for either GPS or cell coverage can be compromised quite a few times out of each & every minute, and all those little 'signal losses' that might each skip a fraction of a mile or so can easily add up to a 'loss' of 30 miles or more out of every 170 miles or so actually travelled. And the faster you are travelling in those areas, the more often it can mean that you get some of those little GPS &/or cell coverage losses that all add up to feed the growing discrepancy between your odo/trip meter & whichever system you are using that relies on GPS &/or cell coverage.... :banghead:
So unless the Rever app is measuring distances based on the signal from a high end GPS with inertial nav, then there's a good chance that even if your odo/trip meter has a less than 10% discrepancy &/or if you spun up that rear tire a few times thru the day, your Trip meter is still going to be the device with the most accurate reading of how many miles you actually travelled over the day's ride! :thumbup:
hyea:
