Press the input shaft rear bearing into the gearbox housing housing, placing a 1 mm thick ring on the clutch side. Measure the depth of the gearbox housing, i.e. the distance between the mating surface of the crankcase and the end face of the bearing.
Determine the thickness of the adjusting ring, based on the value obtained and the markings on the input shaft (see photo).
Install the selected adjusting ring on the input shaft and press the front shaft bearing out of the gearbox housing housing.