Gearbox shape (page 2 of 2)

Controls and forks

To reduce friction and increase accuracy of gear engagement, the gearbox has been provided with a spherical control (1) which transmits movement to the selector prong (3) through a shaft (2).

The selector prong actuates the sliding rods (5) carrying the synchronizer sleeve control forks (4, 6, 7, 8).

Therefore a fork (4) and relative rod provide for the engagement of 1st and 2nd speed, another (F) for the engagement of 3rd and 4th speed, another (7) for engagement of 5th speed and a final one (8) for engagement of reverse speed.

1. Spherical control
2. Shaft
3. Selector prong
4. 1st and 2nd speed engagement fork
5. Sliding rods
6. 5th speed engagement fork
7. 3rd and 4th speed engagement fork
8. Reverse gear engagement fork

An important characteristic of the forks (A) is that the thrust centre coincides with the centerline of the sleeve in order to prevent crawling during speed engagement. This coincidence is not present on forks of conventional gearboxes (B).