This is a Koenigsegg Jesko.

It’s a Koenigsegg, so it’s very fast, very expensive, has fancy doors and you’re unlikely ever to see one.

Also, being a Koenigsegg, it has things that are unusual and interesting. One of these is the nine speed gearbox, which has six gears.

You what? Yes, it’s a six speed nine speed. As explained by Herr* von Koenigsegg, it’s a bit like a dérailleur gear set on a bike. This can have two or three chain wheels at the pedal end and rather more at the wheel end. These work in combination so three front and six rear wheels give you 6x3 or 18 gears.

The Koenigsegg LST in the Jesko works in a somewhat similar manner in that has two sets of gears which interact with each other. Here’s a picture.


It’s not terribly clear but the box has three shafts. One is the input shaft, one is the output and finally there’s an intermediate shaft which has six gears. Three of these mesh with three wheels on the input and the other three with the same number on the output. Each of these six pairs has a multiplate clutch to connect it to a shaft - much like a conventional gearbox but with synchromesh cones and dog teeth replaced by clutches.

Power goes to the input shaft, is transferred to the intermediate shaft by whichever of the three gearsets has its clutch engaged and goes from there to the output shaft by one of the remaining three gearsets. There are three choices in each case so 3x3=9 speeds.


Want to head astern? You’ll be needing the seventh clutch and its associated reverse gear.

To proceed manually in your Jesko, you just push or pull this lever and the next speed up or down is engaged in a small number of milliseconds. To request the electronics to choose their own gear, you just move the lever (or paddle as desired) one step further.


* yes, they use Herr in Sweden too.