Red bull stated that a partial cause of Verstappen's pre-race accident last weekend was do to the flat out throttle synchronising of eighth gear procedure.
Because of the seamless shift technology, two gears are both engaged at the same time for a brief moment. The shift is done in 10-20ms. The powerunit ECU can pinpoint the exact moment of shifting and needs just a minimal amount of torque reduction during shift. Gearsync
Without gearsync shifting is slower, has more torque reduction, takes more time.
Two gears are engaged at the same time but while one is transmitting power the other is free-wheeling. At the same time that the engaged but free-wheeling gear starts to transmit power by having its power transmitting ratchet engaged, two things happen at the same time. The next gear in sequence, depending if up-shifting or down shifting will be engaged but free-wheeling, while the previously engaged gear which was transmitting power will have its power transmitting ratchet disengaged. This gear engagement and disengaging does not involve a moving dog-clutch or selective fork and fork moving selector barrel. The gear engagement and disengaging is all done through the hollow gear shaft with balls activating one of two ratchets inside the respective gear, either a free-wheeling ratchet or a power transmitting engagement ratchet.
