does anyone have any concrete mpg numbers once they added a Thule rack? I just want to know if adding the rack decreased mpg like 1-2 mpg, or like 5-6 mpgs on the highway....as i can certainly deal with a 1-2 mpg loss, i will just drive slightly slower or whatever...but obviously i dont want to take a daily hit of 5-6 mpg... thanks! yes i tried the search....if you feel you cannot respond to this email without sarcasm...then lets be friends!
I had a thule roof rack with front fairing on my last car and there was a definite 1-2 mpg loss with just the rack installed. Quite a bit more with the bikes mounted.
I have the raceway 3 (trunk or hatchback mounted), losing ~ 7-8mpg going the same speed as without rack for the same trip.
I have the Thule Raceway Platform and the one road trip with it I averaged 50.2mpg with two bikes attached. I used cruise control so my mpg for the trip probably was as good as it could have been. The only highway reference trip (not to the same destination) I have is during the break in period, and that was 50.3mpg also using cruise control. Not sure if I will any time soon take the same trip without the Thule attached. It was a trip to the Delaware shore and loved the freedom from the car after we arrived and used our bicycles to get around. But my best guess is that it would only be 2 to 3mpg better in my case driving the same way. Though I am thinking the OP is thinking of the Thule roof rack system. To the OP: if you need a rack for bicycle or added storage you may have to take whatever mpg hit you/we get. One thing to think about is that a 5-7mpg hit on the Prius is not as bad as it it would be on other cars. Using 50mpg as a base, going to 43mpg is only about a 15% reduction. For a 400 mile trip at $4 a gallon for gas the difference is about $5 in gas. So other than hurting our Fuelly averages, the real cost is minimal compared to the cost non-Prius drivers will see.
I was just asking out of pure laziness. I have always had racks on my cars... mostly for my surfboard, but occasionally for lumber trips to home depot as i don't have a truck, to satisfy my building ADD...and while i "Should" remove the base rack while just commuting to work, you never know when the waves will hit NH and you have to be ready...and taking off and putting on the rack all the time seems like a pain, based on all my free time after commuting and trying to wade through corporate america.....
