ALL the gears in a layshaft box excluding perhaps the reverse idler, are thrashing around oil the whole time the vehicle is in motion.Tommy Cookers wrote:....... most interesting !
presumably planetary box losses are only competitive with layshaft box losses in direct drive ?
(all-indirect layshaft boxes are indirect only once whatever the ratio, (eg) how are 3-8 speed planetaries ?)
(I know that's not the main point of this activity)
planetaries were established in bicycles 110 years ago, and were much more efficient than since planet bearing balls were deleted
planetaries were established in motorcycles 100 years ago
(but the motoring world chose layshaft boxes)
In direct gear a planetary set rotates as one 'smooth' unit.
In direct drive a planetary set only needs lube for its support bearings.
If there were no need for oil for operating clutches etc the support bearings could be sealed and the gear teeth would only need spray lube when under load in each gear, not when locked stationary.
You could even air cool the geartrain internaly and in F1 use the airflow for DF benefits.
Layshaft 'burst' loads are offset which is weak, they are fully balanced in a planetary set.
This means the gear caseing will be a far better design and fewer bearings will be needed.
Like my developments the Hobbs box made use of these and other benefits, its problem was the rubber bags used to apply the clutches and its limitation to low input torque figures.
The motoring world did not completely choose layshaft gearboxes only the European part because of the lack of investment. There are plenty of planetary gearboxes in American automatics.
Both ways were way below the potential for planetary geartrains, even 30 years ago.