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      09-01-2020, 05:43 AM   #3

Drives: BMW i8
Join Date: Feb 2019
Location: Eldersburg, MD

iTrader: (0)

Originally Posted by MolarBear View Post
Am I right in thinking that the electric gearbox cannot change gear whilst in use - either it's stuck permanently in first gear in edrive mode up to 75mph, or stuck in second gear in all other modes with no maximum speed?
The electric gear box shifts between 1st and 2nd when in eDrive when there is no load on the gear box.

From the i8 Technical Training guide:

"The shifting of the two gears is assumed by the gear selector actuator. This consists of a 12 V direct current motor and a spindle gear. The spindle gear converts the circular movement of the engine into a linear movement and moves the gearshift fork.

The gears are always shifted without a load. Before the gear shift the load of the electrical machine is withdrawn. After the gear is disengaged by the gear selector actuator, the speed of the electrical machine is adjusted to the gear being shifted. The speed adjustment and the activation of the electrical machine is effected by the EME. Then the gear selector actuator engages the new gear. Only after the PLCD sensor confirms the engaging of the gear and the speed of the electrical machine has been adapted by the EME, is the load of the electrical machine increased again. The driver can generally not notice the entire gear shift. In the event of a failure of the gear selector actuator or the EME, the gearshift fork remains in the current position."
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