Advertise on Bikeforums.net



User Tag List

Results 1 to 7 of 7
  1. #1
    Nikon Nemisis Hawkphoto's Avatar
    Join Date
    Jul 2002
    Location
    Bay Area, California
    Posts
    244
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Bike Racks & Gas Mileage?

    Hey,

    The realization is just now hitting me that I am not getting the same gas mileage that I was getting before I mounted my new Yakima Bike Rack on my car! It seams that I'm getting anywhere from 10 - 20% less mileage out of a tank of gas! I have 2 bike carriers and 2 wheel holders (folded down) AND the Spoiler!!!

    What gives? Anyone else out there have similar experiences?

    Mike
    "I WIll Shoot You On Site!" ;)

  2. #2
    Gravity Is Yer Friend dirtbikedude's Avatar
    Join Date
    May 2002
    Location
    "Over the Hill" and going down fast in the 805.
    My Bikes
    Scott Gambler, Scott Ransom, Kona Bear, Bianchi 928 Carbon/Chorus, C'Dale Rize4
    Posts
    2,961
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I am by no means expert in aerodynamics but it would seem to me that the addition of the spoiler on the front of the rack would change the flow of wind over the car. Thus changing the wake and causing the wind to have a steeper decent off the back of the car producing more drag that the car will need to over come.
    Try taking the spoiler off the front and see if it changes.

    Slainte

  3. #3
    Kev
    Kev is offline
    Senior Member
    Join Date
    Nov 2001
    Posts
    1,652
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    There is alot of drag caused by bike racks, especialy roof racks. I read something a while ago, without any bikes they add 5-10% more wind drag to you're car. So this would atelast hurt your gas mileage by 5-10% min.. probably more.

  4. #4
    Huachuca Rider webist's Avatar
    Join Date
    Jun 2002
    Location
    Charlotte, NC
    My Bikes
    Fuji CCR1, Specialized Roubaix
    Posts
    4,274
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My son in law drives 80 miles round trip daily to work. Says the racks not only hurt feul mileage, but add to the wind noise. Claims it's worth it though to be able to have his bikes with him when he wants to. I use a rack which is removable between trips and attaches at the back of the vehicle. I've noticed no change in feul mileage. Must be the roof racks.
    Just Peddlin' Around

  5. #5
    I drink your MILKSHAKE Raiyn's Avatar
    Join Date
    Jul 2002
    Location
    St. Petersburg, FL
    My Bikes
    2003 Specialized Rockhopper FSR Comp, 1999 Specialized Hardrock Comp FS, 1971 Schwinn Varsity
    Posts
    15,071
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Happens that way. That's why my girlfriend and I use a Saris Bones Rack: put it on take it off, no problem.

  6. #6
    山馬鹿 Spire's Avatar
    Join Date
    Feb 2002
    Location
    Fuchu, Tokyo, Japan
    My Bikes
    TREK 1000 and a junk bike with a basket on the front to go to the shops.
    Posts
    1,398
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Racks will have an impact on city driving, because they increase the mass of the car. If your bikes and rack weight 100 pounds and your car weighs 2000, then your fuel economy will be down about 5% for city driving. For high speed driving (highway speeds) the vast amount of the drag is on the front of the car rather than the back (which is why so many cars have vertical or near vertical rears). Adding a bike rack should not make a huge difference for a car. For a SUV, the difference should almost be neglibile.
    http://www.cyclistsroadmap.com/eng/ - Cyclists' road map. Checkout which roads are good for cycling and rate roads in your area.

  7. #7
    Guest
    Guest
    I've owned top mount Yakima's with wind deflector... Forget gas milage if you're going or gone this route... The wind deflector has minor affect.

    I recently purchased an SUV... and a Thule 4bike outragious hitch mount rack, much easier to mount the bikes and swings out of the way for back door entry...and for those worried about milage, has little affect, because it's behind the vehicle.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •