Why can't you tow the SE on a dolly with the front wheels off the ground?

Any car can spin around on any surface with the right inputs (aka trail braking if done intentionally lol).

Everything I've read and experienced says too much rear brake leads to instability, too much front brake leads to understeer. Rear brakes help reduce stoping distance but don't improve stability.

• "Warning - having too much rear bias can make your car very unstable."
• "too much rear brakes will tend to cause the car to spin; too much front and car will not turn in."
• "Oversteer is caused when the rear wheels lock up first; understeer is the opposite and occurs when the car is front biased"
• "When braking, weight transfers from the rear to the front. This increases traction in the front and reduces it in the rear. If the brakes had a 50/50 balance, the rear wheels would lock up first. This could cause a dangerous spin... NOTE: OEM brake systems are often designed with 5-10% additional front bias. This increases stability but slightly increases stopping distance."

More anecdotal evidence:

I have an annoying squeak coming from the rear brakes when turning right. The slightest amount of brake pressure makes the squeak stop but I have to press the brake pedal, regen alone won't do it.

I've intentionally tested stability on straight black ice. Any brake application triggered the very noticable ABS pulsing to prevent lockup but regen only resulted in perfectly smooth (stable) stops thanks to the precise electric motor control

 

Good to know.

 

Back to the original topic of this thread...

ICE MINIs allow for dolly towing but the BEV doesn't even though the rear is basically identical.

My guess is that MINI decided there was an increased risk of battery puncture from road debris with the car angled upwards behind another vehicle and it was better to ban dolly towing than deal with the potential negative media attention from an EV fire.

 

I just posted this in another thread as well, but Regen does not use friction brakes at all.

To test I literally unplugged at 100%, pulled out the garage, immediately went to about 55mph down my road and then just let off, full Regen to a stop, parked and checked the temps and touched the rotors. Regen does not use friction brakes.

DSC on the hand does, and that is why everyone is seeing brake dust, especially more so on the rear wheels.

Neat trick, wash your car, and then fully disable DSC for a week, boom no brake dust.

As far as where the energy goes I do not know, possible that do to the mini only using a certain percentage of battery vs true capacity and it can actually take the extra charge. Not like your gonna over charge it with Regen to begin with...

 

Regen doesn’t fully regenerate the amount you used to pull out of your driveway and bring it up to 55, so you made room for those electrons!

 

Lol exactly

 

It is all about the Law of Conservation of Mass and Energy. A significant amount of energy is consumed in accelerating and driving at any speed. The regeneration from slowing to a stop, even on a downhill, is not likely to return as much to the battery.


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I responded to the other thread with the manual section that does say brakes are sometimes used during regen.

The problem with regen at high SOC isn't that you're going to over charge the battery, it's the C rate. Fully charged batteries (or cold batteries) do not like high current and full strength regen sometimes goes over what they're able to accept. MINI decided to avoid limiting regen (like Tesla used to) to create a consistent driver experience by blending in the brakes. Tesla now does the same thing as well

 

Chevy hasn’t made this leap. My Bolt definitely does not slow as quickly with a full charge. It’s actually unnerving at first if you are used to always having one-pedal driving.


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