I have racechrono on a HTC One Mini + qstarz bt-q1000xt for 10hz logging.
Over the last few race meets I have been getting major incorrect timing. Circuit laptimer (AMB 260) results can show that I am up to 2s faster than the recorded time. This can vary and its not always incorrect.
I thought this could not really happen if you are using the GPS timestamps.
Comments
Normal accuracy with carefully placed receiver should be less than +-0.1s.
I recommend installing the device to dashboard (car), helmet (kart) or tail section (bike), and maybe look for a better receiver, such as Garmin GLO.
Ile check the trajectories and see how they are.
Ile look at the garmin unit too.