diff --git a/common/speedometer.cpp b/common/speedometer.cpp
index c68b20a..a24d685 100644
--- a/common/speedometer.cpp
+++ b/common/speedometer.cpp
@@ -110,7 +110,7 @@ void Speedometer::computeSpeed() {
     // TODO : done
     //Distance run with one pedal turn = tray size / rear gear size * circumference of the wheel
     constexpr float ms_in_hour = static_cast<float>(3600 * 1000);
-    float pedal_rotation_per_hour = ms_in_hour / static_cast<float>(_pedalRotationTime.count());
+    float pedal_rotation_per_hour = ms_in_hour / std::chrono::duration_cast<std::chrono::milliseconds>(_pedalRotationTime).count();
     float gear_ratio = static_cast<float>(kTraySize) / static_cast<float>(this->_gearSize);
     float wheel_dist_km = static_cast<float>(this->kWheelCircumference) / 1000.0;
     this->_currentSpeed = gear_ratio * wheel_dist_km * pedal_rotation_per_hour;
@@ -141,4 +141,4 @@ void Speedometer::computeDistance() {
     _lastTime = _timer.elapsed_time();
 }
 
-}  // namespace bike_computer
\ No newline at end of file
+}  // namespace bike_computer