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Driveshaft disconnect against high RPM? (4wd split dual motor setup?)

898 Views 7 Replies 3 Participants Last post by  Swing
I am wondering how feasible it would be to have a 4wd setup in which you gear the front axle different from the rear axle. Much like a Tesla passenger car does, or now the Semi.
Ideally you would do that in a way that you stay in the RPM range that the motor is allowed to mechanically make.
The Tesla Semi dual motor axle doesn't even stay in the range of the high RPM motor (goes even higher) and disconnects the motors.

That could be followed for a 4x4 perspective. Most preferably a short geared motor on the rear axle and a long geared motor on the front axle.
Than the rear axle might disconnect once it is doing a higher speed than lets say a Hyper9 is allowed (6k rpm).

What you can find are rear driveshaft disconnects (with levers). Not only are they manually operated, it won't work to disconnect and connect while driving.
Are there any other creative options?
Preferably something automatic.

I thought about using front axle with automatic free locking hubs, but I believe that is not how they work. They will stay engaged until you reverse I think?
Or they might actually release earlier than reversing, but not early enough.

I guess an electronically controlled or automatic disengage of the rear drive shaft would be the best, but it has to be capable of doing that during driving.
So it should be some kind of clutch based system? Or even planetary wheels?

I couldn't find anything on the forum but may have used the wrong search terms.
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Why? You have two motors' worth of torque.

There have been a lot of pics of Semis broken down by the road over the past month or two. Maybe that disconnect is a major reliability hit?
Again, you have not explained what you are trying to accomplish.

"Just to get the power down",

"operating better in the range it is mostly used in",


"it is interesting for higher rpm motors that deliver much relatively late in the rpm band"

all do not state what you are trying to accomplish with all this complexity.
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