Koenigsegg has posted on social media a photo of a nine-speed Light Speed Transmission (LST) “robot” designed specifically for the Jesko. The work of engineering consists of six gear pairs, eight wet multi-plate clutches, including the differential, and three pinion shafts instead of the two in conventional DCT boxes. The clutches in the LST close and open simultaneously, in two milliseconds, and the gear change takes place in 20-30 milliseconds. In this case, the box is able to jump over several steps, while the sequential “robots” can only jump to the next one.
The LST transmission is Koenigsegg’s second completely in-house development after Direct Drive. The company considered the usual preselective “robot” with two clutches too heavy, so they figured out how to replace it. LST weighs only 90 kilograms, one third less than conventional DCT boxes. The unit does not have synchronizers, but it has eight multi-disc clutches in an oil bath and three gear shafts.
A box can jump over several steps at once, when ordinary DCTs move only to an adjacent one. Responsible for this is the Ultimate Power on Demand (UPOD) system, which compares vehicle speed and engine rpm and activates a gear that is beneficial for “explosive” acceleration. Since all the clutches open and close at the same time, the change of stages occurs “lightning fast”, somewhere in 20-30 milliseconds.
The shift mechanism of LST is dual-mode: a light press on the paddle shifters or the transmission selector changes the gear to the next one, if you push it harder, UPOD will work, and the box will jump to the optimal gear for acceleration, for example, from seventh to fourth.
There are nine gears in total, plus one reverse gear. The reverse is realized through the main clutch, which matches the input shaft with the output, bypassing the set of gears.