Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation:
    Join Date
    Aug 2008
    Posts
    174

    Preston FR Seatpost Question

    This may be a bad idea so I'm looking for some feedback. I have a 2009 Preston FR and it uses a 30.0mm seatpost with a 34.9mm outer diameter on the seattube. Can I bore out the seattube to 30.9mm so I can use the Joplin 4 remote adjustable seatpost that I already have on another bike. I see lots of bikes that have an O.D. of 34.9 and inner diameter of 31.6, so I think it would be ok. Besides my 30.0 seatpost is a little loose anyhow so I probably don't have to get it bored out too much. I love the Preston and I think the Joplin would be perfect for this bike.

  2. #2
    mtbr member
    Reputation:
    Join Date
    Dec 2007
    Posts
    122
    i have the same frame and though it sucks having and odd seatpost i wouldn't even consider boring out the tube.you'll be weakening the tube big time. im sure if you bored the tube you can kiss any warranty from transition good bye.

  3. #3
    Basura Blanca
    Reputation:
    Join Date
    Jan 2004
    Posts
    1,750
    I think I'd look for a 2nd opinion to woody's first. Warranty issues aside (you probably didn't pay full boat for a 2009 Preston anyway), I'd certainly be willing to take a chance on making it work. But for the beer money you'd spend getting a buddy to ream 0.7mm out of the ST and 0.2 off the Joplin post (yes, I'd "share" the material loss between the 2), you might come out cheaper getting someone to mill you an extra-long shim so that you can run an All Mountain Post (27.2mm).
    - Joe

  4. #4
    mtbr member
    Reputation:
    Join Date
    Aug 2005
    Posts
    1,647
    There are several dropper posts in 27.2. That would be the safest way to go.

  5. #5
    The Sentinel
    Reputation: mtnbiker62's Avatar
    Join Date
    Jan 2004
    Posts
    530

    I have a shim...

    I'm in the process of selling my 2005 Preston, and I have a 27.2 shim that I won't be needing...pm me if you are interested.
    Sworn to avenge, condemned to hell

  6. #6
    Basura Blanca
    Reputation:
    Join Date
    Jan 2004
    Posts
    1,750
    Agreed, but to be truly safe, you'd want to make sure the shim extended about an inch past the ST-TT junction. On my size large frame, the off-the-shelf 100mm shims were not long enough.
    - Joe

    Quote Originally Posted by MaddSquirrel
    There are several dropper posts in 27.2. That would be the safest way to go.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Aug 2008
    Posts
    174
    At this point I think I'll look into a 27.2 adj. seatpost with a shim. I hate to have to buy a new seatpost since I have the Joplin but its probably the best way to go. Or maybe I'll keep the X-C bike ( a Maverick Matic) and leave the Joplin on it and just use the Preston for light DH and FR days. I never thought how much the Joplin would change the way I ride but now I'm lost without it for X-C/all-mountain riding.

  8. #8
    Shikaka!
    Reputation: ace_ventura's Avatar
    Join Date
    Oct 2006
    Posts
    139
    You know that soon there should be a version of the KS seat post in 27.2 diameter. Only annoying thing about it, is that it utilizes a reservoir tank to compensate for the thinner seat post. Ultimately, it ends up a bit bulkier than the 30mm versions. I have a 2009 Preston which I'm about to sell in favor of the new Covert, which of course, is compatible with 31.9 seat posts, so problem solved. Messing with shims and stuff sounds like a headache IMO.

  9. #9
    Deadhead
    Reputation:
    Join Date
    Mar 2004
    Posts
    354
    I know a Bottlerocket owner who did the seattube ream thing to fit a 30.9 Gravity Dropper and has had zero issues. I'm pretty sure he mentioned getting the OK from Transition before doing it; can't remember what the deal was with the warranty side of things though. Maybe he'll post up the details.
    "If you can get both wheels sliding with no brakes, that's when you really know that you're cookin." Nathan Rennie

  10. #10
    mtbr member
    Reputation:
    Join Date
    Mar 2004
    Posts
    427
    Quote Originally Posted by gratefulbiker
    I know a Bottlerocket owner who did the seattube ream thing to fit a 30.9 Gravity Dropper and has had zero issues. I'm pretty sure he mentioned getting the OK from Transition before doing it; can't remember what the deal was with the warranty side of things though. Maybe he'll post up the details.
    Tim did have that done to his bottle rocket and he is currently shredding the hell out of Winter Park with no problems
    CAMBr West
    Gives us a couple bucks and we'll give you some trails with sweet jumps and stuff.

Posting Permissions

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