Seatpost sizing?

LAUNCH69
LAUNCH69 Posts: 119
edited March 2010 in MTB workshop & tech
Hi there,
The specs on my 2008 Rockhopper say that my seatpost size is 30.9mm. However I have a nice, shiny seatpost that is 27.2mm. Will it fit or can it be made to fit? Please help!
Specialized Rockhopper

Bike is still better than the rider . . .

Comments

  • redvee
    redvee Posts: 11,922
    The 27.2mm will fit in the seattube but don't expect it to be of any use. If the specs say 30.9mm then 30.9mm is the size you need.
    I've added a signature to prove it is still possible.
  • nicklouse
    nicklouse Posts: 50,675
    if you want to use your new post you will need to find a shim to convert it to 30.9mm
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • LAUNCH69
    LAUNCH69 Posts: 119
    Where could I get shims from? The frame is specialized and the aeatpost is a carbon raceface job.
    Specialized Rockhopper

    Bike is still better than the rider . . .
  • nicklouse
    nicklouse Posts: 50,675
    looked at any of the on line shops?

    most sell shims.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • LAUNCH69
    LAUNCH69 Posts: 119
    thanks for the advice, searching now . . .
    Specialized Rockhopper

    Bike is still better than the rider . . .
  • pastey_boy
    pastey_boy Posts: 2,083
    Viner Salviati
    Shark Aero Pro
    Px Ti Custom
    Cougar 531
    Sab single speed
    Argon 18 E-112 TT
    One-one Ti 456 Evo
    Ridley Cheetah TT
    Orange Clockwork 2007 ltd ed
    Yeti ASR 5
    Cove Hummer XC Ti
  • LAUNCH69
    LAUNCH69 Posts: 119
    Are there any negatives to using shims?
    Specialized Rockhopper

    Bike is still better than the rider . . .
  • nicklouse
    nicklouse Posts: 50,675
    nope.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • pastey_boy
    pastey_boy Posts: 2,083
    id say they are a positive thing as they tend to not mark your post as much as inserting it directly into the frame, plus they avoid any corrosion issues that may result in a seized post. also using a thinner post can result in more comfort as they flex more
    Viner Salviati
    Shark Aero Pro
    Px Ti Custom
    Cougar 531
    Sab single speed
    Argon 18 E-112 TT
    One-one Ti 456 Evo
    Ridley Cheetah TT
    Orange Clockwork 2007 ltd ed
    Yeti ASR 5
    Cove Hummer XC Ti