The electronics for this build are relatively simple, based on an Arduino Pro Mini ... Just two zip ties hold this GPS speedometer onto the handlebars, and from the video below, everything looks ...

Instead, this build is an analog display for GPS-acquired speed data ... The display itself is a gutted marine speedometer fitted with the movement from a motorcycle tachometer.

Surely the GPS technology should be more accurate than the speedometer? – RP You’re right that GPS is usually more accurate ...

While they can be affected by poor reception or noise in the radio signal, GPS-based speedometers are generally considered the benchmark for measuring velocity. On the other hand, radar ...