[Polymerman]

We are still trying to figure out how we're going to haul stuff in our new Pro. The VE roof rails are $250. Are there any more affordable rails out there? I am looking to haul a cargo container up there and maybe bicycles.

 

[Don]

I'm sure there will eventually be aftermarket offerings. On an EV, adding things to the roof which disturb airflow over the car will give you a much bigger range hit that you're probably thinking, especially if you're driving at speeds over 35 mph or so - At freeway speeds it will be terrible. You might not notice a 3 or 4 mpg decline on an ICE car, but it'll be more obvious on an EV. Wind resistance at high speeds is the enemy of all EV's and objects placed on the roof will change the CD of the car by a larger amount than you might guess

Don

 

[Polymerman]

I'm sure there will eventually be aftermarket offerings. On an EV, adding things to the roof which disturb airflow over the car will give you a much bigger range hit that you're probably thinking, especially if you're driving at speeds over 35 mph or so - At freeway speeds it will be terrible. You might not notice a 3 or 4 mpg decline on an ICE car, but it'll be more obvious on an EV. Wind resistance at high speeds is the enemy of all EV's and objects placed on the roof will change the CD of the car by a larger amount than you might guess

Don

Thanks, that's what I am coming to realize as well on further reading. Seems like a roof container will reduce range around 20% at highway speeds which is too much. It seems like a hitch tray might be a better option?

 

[Don]

I would think so. If what you need to carry will fit on one and not exceed the tongue weight rating of the hitch (250 or 300 pounds? - I really don't know) then it would be a better choice for long range travel. It's one thing to put a kayak on the roof for a 10 mile trip to the river, but another thing if it's for long trips

Don

 

[mochalatte]

Thanks, that's what I am coming to realize as well on further reading. Seems like a roof container will reduce range around 20% at highway speeds which is too much. It seems like a hitch tray might be a better option?

Yep, I got a ~20% efficiency hit with 2 mountain bikes on top (photo in this post) on 55 mph roads.

Mounting the bikes behind the car on any hitch carrier will be much more aero.

 

[JimmyVW]

Thanks, that's what I am coming to realize as well on further reading. Seems like a roof container will reduce range around 20% at highway speeds which is too much. It seems like a hitch tray might be a better option?

20%? My consumption went up about 50% with a roofbox and 2 bikes on the back (hitch). that was while driving a modest 65~67 on the freeway

 

[7S POWER]

Yep, I got a ~20% efficiency hit with 2 mountain bikes on top (photo in this post) on 55 mph roads.
Mounting the bikes behind the car on any hitch carrier will be much more aero.

Any object place on the roof will increase the Cd of the vehicle I.e. roof rails. This is because of the increase in the surface area.

7S POWER

 

[Don]

Any object place on the roof will increase the Cd of the vehicle I.e. roof rails. This is because of the increase in the surface area.

Turbulence increases Cd much more than just surface area - The roof is a huge area and it presents very little drag because it doesn't create turbulence - Even the huge windshield doesn't create much drag. Same with the fore and aft roof rails - They present very little frontal area to the wind because they are aligned with the flow. A couple bicycles up there represent very little surface area, but they create a ton of turbulence

Put a couple of cross rails on the roof rails and you have both more surface presented to the wind and lots more turbulence. I had a Mazda Protege 5 with factory cross rails and they even shaped them a bit like aircraft wings, but they created so much turbulence you could hear the noise at anything above about 50 mph. Mazda replaced them with a new pair which had some turbulence busting appendages, but it hardly helped at all. Many owners just remove the cross rails

Don