Effect of roofrack on mpg

They (Thule) must make about 20 different ones but they all look fairly aerodynamic. I can't give you an estimate because I don't know enough but I'll take a guess, 10 mpg.

Be sure to let us know and it might be nice if you posted a picture of the rack mounted on your Prius.

 

I know you already bought your roof rack,your going to take a mileage penalty I can't hazzard a guess what that will be. Don't mean to pry but What do You plan on loading up there?
I Haul 2 bikes on my GEN II with a hitch mount and I'm not noticing any significant penalty.If your hauling bikes,here's a link:


Bike racks: Tips for choosing the right one for you

I do feel very slight tail sway but i'd be interested in finding out about the handling effects of gear up top.If it's bikes you haul,there's a forum on priuschat that covers all aspects of this.
I've even posted photos of my setup on one of them.If you click on my tag it might lead you to that. Good luck-enjoy your new Prius!:rockon:

 

The major impact from a roof rack is aerodynamic drag, which is related to speed in a non-linear fashion. The rack will cause a much bigger mileage hit at highway speeds than driving around town.

Tom

 

If the mileage hit is that much of a concern, then wait until Curt Mfg or another hitch company makes one for the Gen III. I never liked the roof-mounted racks that much, preferring the hitch racks for my Honda's and Mazda's.

 

Thanks,
I exepected the roof rack to cause big turbulence.I always viewed rear mounted gear in the same way We tuck in behind a tractor/trailer-Get under the slipstream.
There's a vacuum behind a Prius,might as well take advantage of it.The Prius also affords great rear views through it's windows on the rear hatch so you can keep an eye on your gear.
Personally,I do not see any advantage of having gear up top.
But I guess it's a matter of opinion ie:rear mounted gear renders the reverse camera useless and parking clearances limited.
Either way-to each his own! Happy trails

 

I called Curt and they said they should have a hitch available in a couple of weeks. I am waiting for it so I can use my hitch bike rack. I don't like roof racks since they hurt mpg and are really noisy on the highway...even with the fairing.

 

I was considering either the Thule or Yakima to put multiple surfboards up top. For the most part I can stuff them in the car, but when I want to surf with friends, the only place to put them is on the roof.

I also wondered what % of MPG you would lose with roof racks installed.

 

Surfboards are probably less resistant to air flow than an empty Thule rack.That big air diverter on the foreward part of the rack is
there to prime the airflow up and over bulky cargo like suitcases and also happens to serve as a billboard for the manufacturer.
Whatever rack you get-see if you can do without that big panel on the front.

 

If by chance you are only packing "stuff" on your roof and not bikes or kayaks, you could do what we did on our 7,500 mile cross country trip. We packing our tents, sleeping bags, etc. in dry bags laid them right on the roof, tucked in behind the front fairing and side rails. Two adults, two teens, and all the camping gear and we averaged 50 mpg on our trip, okay, not quite, it was only 49.74. We chose to drive 60 mph, which was the critcal point, along with aero packing on top.

PA P

 

I've got Yakima which has round bars, instead of the flat front surface of a Thule. A little impact on MPG with the rack empty, its mostly the gear that creates the drag.

Besides, it's all relative. I consider my PMG (People Miles per Gallon) a lot more than my car's MPG. A couple less mpg with 4 people in the car is more efficient better than full mpg with 2 people and bikes inside since more cars have to make the trip. The rack saves gas.

 

I was thinking of getting Folding Bikes and carrying them inside. zero loss in MPG
Folding Bikes by Citizen Bike