Lucid Air roof box

[Electrified]

Not according to Lucid...110 pounds limit.

Makes no sense, tongue weight is tongue weight, and that comes from experience, I conservatively have 500K miles hauling toys around this country.

There's other threads that talk about this. 6000 lb towing means a 600 lb tongue weight for a **trailer**. That is at a very specific short distance from the attachment pin.

Putting a big box back there multiplies the torsion effect. Thus the reduced weight limit.

I thought it was 5000 Lb., @6K I'm going 600 to 900 Lbs. of tongue weight. Remember a 6K trailer with a 600 to 900 Lb. tongue weight acts like a fulcrum, the longer the tongue wilder shit gets. Keep it short she said LOL

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[johnse]

There was a bit of discussion about this in the Gravity Delivery megathread here's a few of the posts. It all boils down to torque and the length of the moment arm.

I guess they expect customers to use a trailer to haul their bikes. lol.
It is interesting how far from the vehicle the tow ball is. That would seem to violate the whole reason you can't put more than a 110lb bike rack on...
Looks like more than 7.5" I guess it shows no one reads the manual.
View attachment 31069

I think that might be a class 4 ball mount (12,000 lbs, 1 1/4 inch dia ball hole ). Although Lucid doesn't mention it, it looks like they are using a class 3 receiver(7,500 lbs, 1 inch ball hole). Lucid is trying to help you not overload the vehicle.

Perhaps this is what happens when you use class 4 stuff on an 11,000 lb rating vehicle?
www.reddit.com

Was wondering if you could measure X below. I'm guessing the left hole is centered below the vertical pin part and the picture is distorting it. If it's not centered then I'd rather have horizontal distance to the center of the pin part. Scaling your picture I'm guessing about 5.5 inches. With this number you can figure the maximum moment the receiver wants to see which will be (X+7.5)*600LB.
With 5.5 in for X its 7800 in-lb. With this number you can get a guess at the equivalent load for any distance.
So the Lucid picture towing the Airstream trailer I measure a pin to ball distance of ~17 inches. 7800 in-lb/117in = 459 lb. That AirStream mini has a max tung weight of around 440.

The 110 pounds Lucid gets from somewhere equates to 7800 in-lb/110 lb = 71 in. ie approx 6 ft. Perhaps rotation loads around that pin make the difference?
View attachment 31159

The weight of the bicycles also extends upwards from the receiver, and if you are launching, that's a 1g load at several feet from the mounting point. And for most bike racks, all of the mass of the carried items is attached at the upper end of that moment arm.

Whereas when towing, the hitch pin and hitch ball are in alignment, so no extra torsion beyond the tongue weight.

Lucid should add some sort of CAD software to the car so you can simulate your bike and rack.
I can confirm that bike racks can generate very large torques. I bent my Saris rack with 4 bikes on it, though admittedly I was driving quite fast on a dirt road. I drilled another hole to get more insertion depth (though I subsequently sold it and replaced with a OneUp rack.)

View attachment 31162

Searching for "tongue weight" gets several others.