Advertise on Bikeforums.net



User Tag List

Page 1 of 3 123 LastLast
Results 1 to 25 of 52
  1. #1
    occasional cyclist
    Join Date
    Jul 2010
    Posts
    141
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    How much speed/ power penalty from a helmet?

    Had an informal 25 mile competitive session against some random middle-aged guy on the trail, him wearing a cycling cap, me with a helmet. I caught the guy from maybe 400 yds back over about 6 miles, it stayed competitive for maybe the next 14 after that, and I was able to slowly build a 200 yd lead over the final 5 miles. Before you attack me for mercilessly beating the middle-aged guy, I am also a middle-aged guy. He had a newer bike, a Cervelo TT with aero bars and tear drop seatpost, vs my older road bars steel bike, so that should have given him an advantage along with the Vroomen and White design, supposedly worth 5 watts against other newer bikes if you believe the marketing hype. Maybe a fitness difference explains my ability to overcome the disadvantage.

    My question is, comparing a road helmet to an old school cycling cap, it seems obvious that more cross section area dragging in the wind would have some cost. Neglecting the fact that event sanctioning bodies will exclude riders without helmets, can anyone quantify what it costs in terms of speed or power?

  2. #2
    Senior Member MajorMantra's Avatar
    Join Date
    Jan 2009
    Location
    Edinburgh, UK
    Posts
    1,118
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Suburban Grind View Post
    Had an informal 25 mile competitive session against some random middle-aged guy on the trail, him wearing a cycling cap, me with a helmet. I caught the guy from maybe 400 yds back over about 6 miles, it stayed competitive for maybe the next 14 after that, and I was able to slowly build a 200 yd lead over the final 5 miles. Before you attack me for mercilessly beating the middle-aged guy, I am also a middle-aged guy. He had a newer bike, a Cervelo TT with aero bars and tear drop seatpost, vs my older road bars steel bike, so that should have given him an advantage along with the Vroomen and White design, supposedly worth 5 watts against other newer bikes if you believe the marketing hype. Maybe a fitness difference explains my ability to overcome the disadvantage.

    My question is, comparing a road helmet to an old school cycling cap, it seems obvious that more cross section area dragging in the wind would have some cost. Neglecting the fact that event sanctioning bodies will exclude riders without helmets, can anyone quantify
    what it costs in terms of speed or power?
    Racing on the MUP? Your dignity.

  3. #3
    Senior Member zonatandem's Avatar
    Join Date
    Dec 2003
    Location
    Tucson, AZ
    My Bikes
    ariZona carbon fiber tandem & single
    Posts
    9,975
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Zero for speed/power, especially if he has the cap's bill facing backward acting like a spoiler!

  4. #4
    Pentapointed Member ahsposo's Avatar
    Join Date
    Jan 2010
    Location
    On Some Far Away Beach After the Season is Over...
    My Bikes
    A Home Built All Rounder, Bianchi 928, Specialized Langster, Dahon Folder
    Posts
    6,374
    Mentioned
    10 Post(s)
    Tagged
    1 Thread(s)
    Please.

    Somebody shoot me.

    Please!
    Quote Originally Posted by toddles View Post
    If I gotta look up words, it's not worth my time.

  5. #5
    Throw the stick!!!! LowCel's Avatar
    Join Date
    Apr 2003
    Location
    Charleston, WV
    My Bikes
    GMC Denali
    Posts
    17,586
    Mentioned
    12 Post(s)
    Tagged
    1 Thread(s)
    Helmet compared to cycling cap accounts for 13.7 watts. I read it in on the internet so it must be true.....
    I may be fat but I'm slow enough to make up for it.

  6. #6
    Senior Member MegaTom's Avatar
    Join Date
    Jul 2009
    Location
    Orlando, FL
    My Bikes
    Specialized Roubaix SL3, Lynskey Cooper CX
    Posts
    2,013
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    You can't be serious....

  7. #7
    Senior Member Homebrew01's Avatar
    Join Date
    Jul 2004
    Location
    Ffld Cnty Connecticut
    My Bikes
    Old Steelies I made, Old Cannondales
    Posts
    15,505
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by LowCel View Post
    Helmet compared to cycling cap accounts for 13.7 watts. I read it in on the internet so it must be true.....
    I think you rounded up. I read it was 13.68149
    Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike

  8. #8
    Throw the stick!!!! LowCel's Avatar
    Join Date
    Apr 2003
    Location
    Charleston, WV
    My Bikes
    GMC Denali
    Posts
    17,586
    Mentioned
    12 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Homebrew01 View Post
    I think you rounded up. I read it was 13.68149
    I was trying to keep it simple for the 41 characters.
    I may be fat but I'm slow enough to make up for it.

  9. #9
    Senior Member
    Join Date
    Oct 2008
    Location
    Chicago, IL
    My Bikes
    S-Works Roubaix SL2, Secteur Sport, TriCross, Kaffenback, Lurcher 29er
    Posts
    2,391
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Homebrew01 View Post
    I think you rounded up. I read it was 13.68149
    You simply can't calculate 41 with higher precision than this thread.

  10. #10
    Slower Member and1homer's Avatar
    Join Date
    Apr 2011
    Location
    Boulder, CO
    My Bikes
    2009 Giant Defy 1
    Posts
    329
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Did you consider maybe you were the only one on the MUP who was racing? Just a thought

  11. #11
    Senior Member
    Join Date
    Jul 2008
    Posts
    134
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

  12. #12
    Señor Blues on the path's Avatar
    Join Date
    Jul 2009
    Location
    upstate NY
    My Bikes
    CAAD 10
    Posts
    852
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    OP is lucky this isn't a weekday when everybody is slacking at work..
    IMO, FWIW, CFM, YMMV, E PLURIBUS UNUM

  13. #13
    Senior Member
    Join Date
    Dec 2009
    Posts
    4,005
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Doesn't matter. If you're REALLY racing helmets are mandatory.

  14. #14
    Blissketeer HokuLoa's Avatar
    Join Date
    Aug 2007
    Location
    USA
    Posts
    1,309
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    oh brother...

  15. #15
    Zoom zoom zoom zoom bonk znomit's Avatar
    Join Date
    Sep 2006
    Location
    New Zealand
    My Bikes
    Giant Defy Composite,Trek 1.7c, Specy Hardrock, Nishiki SL1, Jamis Commuter
    Posts
    2,835
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I always just wear a cap when I'm on my recovery rides.

  16. #16
    RidingLikeCrazy! rangerdavid's Avatar
    Join Date
    Jun 2009
    Location
    Boone, North Carolina
    My Bikes
    2009 Cannondale CAAD9-6
    Posts
    4,932
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by LowCel View Post
    I was trying to keep it simple for the 41 characters.


    not simple enough unless it comes with crayons and a coloring book
    *********************************

    Rangerdavid

    2009 Cannondale CAAD 9-6
    2005 Raleigh M40


    Riding the mountains of North Carolina

    I do today what you don't , so I can do tomorrow what you can't

    "Absolutely imbecilic. But typical." ..... pcad

  17. #17
    Senior Member WhyFi's Avatar
    Join Date
    Jan 2010
    Location
    Got a castle in - er, Minneapolis, that's where I dwell!
    My Bikes
    2009 Jamis Xenith
    Posts
    9,130
    Mentioned
    36 Post(s)
    Tagged
    0 Thread(s)
    100 watts, just like my Sanyo stereo, baby.
    Quote Originally Posted by RollCNY View Post
    I would wager that not riding in Minnesota is just as fatiguing as not riding in New York.

  18. #18
    Senior Member Homebrew01's Avatar
    Join Date
    Jul 2004
    Location
    Ffld Cnty Connecticut
    My Bikes
    Old Steelies I made, Old Cannondales
    Posts
    15,505
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    I'm considering removing the streamers from the ends of my handlebars due to the additional watts they add. Thoughts?
    Does anyone make thin, colored carbon fiber streamers that are more aero than the standard plastic streamers I'm using now ?
    Bikes: Old steel race bikes, old Cannondale race bikes, less old Cannondale race bike, crappy old mtn bike

  19. #19
    Senior Member WhyFi's Avatar
    Join Date
    Jan 2010
    Location
    Got a castle in - er, Minneapolis, that's where I dwell!
    My Bikes
    2009 Jamis Xenith
    Posts
    9,130
    Mentioned
    36 Post(s)
    Tagged
    0 Thread(s)
    What color are they?
    Quote Originally Posted by RollCNY View Post
    I would wager that not riding in Minnesota is just as fatiguing as not riding in New York.

  20. #20
    Senior Member halfspeed's Avatar
    Join Date
    Nov 2003
    Location
    SE Minnesota
    My Bikes
    are better than yours.
    Posts
    10,854
    Mentioned
    37 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by whyfi View Post
    100 watts, just like my sanyo stereo, baby.
    bpc ftw.
    Telemachus has, indeed, sneezed.

  21. #21
    Senior Member echotraveler's Avatar
    Join Date
    Aug 2009
    Posts
    1,771
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    wow! OP PLZ DELETE!

  22. #22
    Senior Member
    Join Date
    Jan 2009
    Location
    North Denver
    Posts
    115
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Fitness difference? seriously? You gained 200 yards in 25 miles? Thanks for the laugh

  23. #23
    Senior Member Crimsonghost's Avatar
    Join Date
    Sep 2010
    Location
    San Francisco, CA
    Posts
    213
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Homebrew01 View Post
    I'm considering removing the streamers from the ends of my handlebars due to the additional watts they add. Thoughts?
    Does anyone make thin, colored carbon fiber streamers that are more aero than the standard plastic streamers I'm using now ?
    Sad thing is I really do have some carbon fiber cloth in my lab.

    Im sure there's a practical application for this somewhere. Think streamers are too much on a Cervélo? They don't match the paint, but I'm sure they will make me look über fast.

  24. #24
    What's a bike? adclark's Avatar
    Join Date
    Sep 2009
    Location
    USA
    My Bikes
    Bianchi Veloce
    Posts
    615
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    It doesn't cost you anything because when you crash and hit your head, you can probably not suffer any long term damage. I doubt the cycling cap will do the same, so you would be far more likely to miss time on the bike.
    The cake is a lie...

  25. #25
    What's a bike? adclark's Avatar
    Join Date
    Sep 2009
    Location
    USA
    My Bikes
    Bianchi Veloce
    Posts
    615
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by rangerdavid View Post
    not simple enough unless it comes with crayons and a coloring book
    The cake is a lie...

Page 1 of 3 123 LastLast

Posting Permissions

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