Go Back  Bike Forums > Bike Forums > Classic & Vintage
Reload this Page >

Seatpost problem

Notices
Classic & Vintage This forum is to discuss the many aspects of classic and vintage bicycles, including musclebikes, lightweights, middleweights, hi-wheelers, bone-shakers, safety bikes and much more.

Seatpost problem

Old 10-20-11, 01:25 PM
  #1  
atmdad
Oh Snap, not again...
Thread Starter
 
atmdad's Avatar
 
Join Date: Mar 2010
Location: Cardiff, Ca
Posts: 608
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Seatpost problem

No, not another stuck seatpost thread. Actually the opposite. I ordered the wrong size, just a gnat's ass too narrow, and I don't want to deal with the return/shipping/wait for the new one. With the binder bolt pretty much fully tightened I can snug it up while on the stand but it is not tight enough to actually ride on. I was thinking just making up a shim from an aluminum can should be enough. Who here has done this and is it a reasonable workaround?
atmdad is offline  
Old 10-20-11, 01:40 PM
  #2  
zukahn1 
Senior Member
 
zukahn1's Avatar
 
Join Date: Oct 2011
Location: Fairplay Co
Posts: 8,175

Bikes: Current 79 Nishiki Custum Sport, Jeunet 620, notable previous bikes P.K. Ripper loop tail, Kawahara Laser Lite, Paramount Track full chrome, Raliegh Internatioanl, Motobecan Super Mirage. 59 Crown royak 3 speed

Mentioned: 21 Post(s)
Tagged: 1 Thread(s)
Quoted: 482 Post(s)
Liked 286 Times in 177 Posts
I would check your LBS and online for a seat post shim if you look you can find 1mm and 2mm shims for most seat posts that are made for this problem.
zukahn1 is offline  
Old 10-20-11, 01:55 PM
  #3  
Old Fat Guy
Banned
 
Join Date: Jan 2007
Posts: 5,280
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Depends on the frame and post. Maybe sell the wrong size at a discount, get the right size, and consider it a cheap lesson learned.

Shims will work, standard on some Schwinn's (Le Tours?). I wouldn't use them on a really nice bike or a really nice post.
Old Fat Guy is offline  
Old 10-20-11, 02:23 PM
  #4  
jimmuller 
What??? Only 2 wheels?
 
jimmuller's Avatar
 
Join Date: Apr 2010
Location: Boston-ish, MA
Posts: 13,337

Bikes: 73 Raleigh Carlton Gran Sport, 72 Peugeot UO-8, 82 Peugeot TH8, 87 Bianchi Brava, 76? Masi Grand Criterium, 87 Centurion Ironman Expert, 74 Motobecane Champion Team, 86 & 77 Gazelle champion mondial, 81? Grandis, 82? Tommasini, 83 Peugeot PF10

Mentioned: 183 Post(s)
Tagged: 0 Thread(s)
Quoted: 1190 Post(s)
Liked 288 Times in 145 Posts
What size is it exactly?
__________________
Real cyclists use toe clips.
With great bikes comes great responsibility.
jimmuller
jimmuller is offline  
Old 10-20-11, 02:50 PM
  #5  
bikingshearer 
Crawlin' up, flyin' down
 
bikingshearer's Avatar
 
Join Date: Jan 2006
Location: Democratic Peoples' Republic of Berkeley
Posts: 4,190

Bikes: 1967 Paramount, 1982-ish Ron Cooper,1978 Eisentraut "A," mid-1960s Cinelli Speciale Corsa, 1961 Bianchi Competizione (an Eroica bike), 1994 Trek 520, 199? Burley Bossa Nova, early-1970s Cinelli Speciale Corsa (also an Eroica bike)

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 345 Post(s)
Liked 354 Times in 190 Posts
Yeah, I've done it many, many moons ago. I cut up an old Coke can and used trial-and-error to get the fit. It worked just fine. Not the most asthetically pleasing solution, but it will work.

I thought I was off by .2mm, but it turns out I was .4mm off. Based on my experience, the issues I see are: (1) the shim I ended up with was pretty narrow, so if you are only off by .2mm your shim will be very narrow; and (2) if the top of your seat lug has a shaped profile (as opposed to a square-cut profile), you will have an appearance issue when you bend the shim to hang it on the seat lug so it doesn't fall into the bootom bracket.
__________________
"I'm in shape -- round is a shape." Andy Rooney
bikingshearer is offline  
Old 10-20-11, 03:06 PM
  #6  
Reynolds 
Passista
 
Reynolds's Avatar
 
Join Date: Jul 2005
Posts: 7,218

Bikes: 1998 Pinarello Asolo, 1992 KHS Montaña pro, 1980 Raleigh DL-1, IGH Hybrid, IGH Utility

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 722 Post(s)
Liked 381 Times in 220 Posts
In my experience, the shim will work if it's not too thin (about 0.4 mm, for a total of 0.8). A thin shim would probably be deformed while inserting the seatpost. If I were you, I'd get a properly sized seatpost.
Just my .02.
Reynolds is offline  
Old 10-20-11, 03:56 PM
  #7  
atmdad
Oh Snap, not again...
Thread Starter
 
atmdad's Avatar
 
Join Date: Mar 2010
Location: Cardiff, Ca
Posts: 608
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by jimmuller View Post
What size is it exactly?
Well, if I new, I wouldn't be here asking about a shim now would I.

Just kidding.
I did measure the frame with calipers before I ordered at 1", but considering seat post sizes vary by 10ths of millimeters, I'm fairly confident I didn't measure it exactly. OFG nailed it, an old Schwinn Le Tour that i'm building up as townie/errand runner/bar beater bike mostly with parts on hand thus aesthetics are not high on the list.

Since several of you aren't completely shooting done the shim idea i'm gonna give it a try first.

or maybe...hummmm

does anybody know if JB Weld bonds steel and aluminum?
atmdad is offline  
Old 10-20-11, 03:58 PM
  #8  
Old Fat Guy
Banned
 
Join Date: Jan 2007
Posts: 5,280
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 1 Time in 1 Post
I may have one of those shims laying around, if I do, yours for postage.

Edit: Just checked, It must have been tossed in with the boxes of crap I've been selling, I have purged most of my flipper fodder. It has a lip around the top, to keep it from falling into the seat tube, somebody here should have one.

Last edited by Old Fat Guy; 10-20-11 at 04:04 PM.
Old Fat Guy is offline  
Old 10-20-11, 04:06 PM
  #9  
atmdad
Oh Snap, not again...
Thread Starter
 
atmdad's Avatar
 
Join Date: Mar 2010
Location: Cardiff, Ca
Posts: 608
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Thanks, i'll keep that in mind.
atmdad is offline  
Old 10-20-11, 04:07 PM
  #10  
due ruote 
Senior Member
 
due ruote's Avatar
 
Join Date: Dec 2006
Posts: 7,344
Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 774 Post(s)
Liked 263 Times in 178 Posts
I've done the soda can shim and it worked fine, although the shim is so thin and the fit so snug (if you get it right) that it's a bit of a challenge to fit everything together without crinkling or tearing the shim. At least they're cheap so if it takes several tries, no biggie.

A soda can is thin enough that once you get everything set and tightened, you can take an x-acto around the top of the seat lug and cut the remainder away so it doesn't show.
due ruote is offline  
Old 10-20-11, 04:14 PM
  #11  
jimmuller 
What??? Only 2 wheels?
 
jimmuller's Avatar
 
Join Date: Apr 2010
Location: Boston-ish, MA
Posts: 13,337

Bikes: 73 Raleigh Carlton Gran Sport, 72 Peugeot UO-8, 82 Peugeot TH8, 87 Bianchi Brava, 76? Masi Grand Criterium, 87 Centurion Ironman Expert, 74 Motobecane Champion Team, 86 & 77 Gazelle champion mondial, 81? Grandis, 82? Tommasini, 83 Peugeot PF10

Mentioned: 183 Post(s)
Tagged: 0 Thread(s)
Quoted: 1190 Post(s)
Liked 288 Times in 145 Posts
Originally Posted by atmdad View Post
Well, if I new, I wouldn't be here asking about a shim now would I.

does anybody know if JB Weld bonds steel and aluminum?
I was just wondering if you'd gotten a French seatpost for a non-French bike. Measure it to the nearest 0.1mm, and I (or someone else) might be willing to take it off your hands.

I wouldn't JB Weld the seatpost in place, if that's why you're asking.
__________________
Real cyclists use toe clips.
With great bikes comes great responsibility.
jimmuller
jimmuller is offline  
Old 10-20-11, 04:50 PM
  #12  
atmdad
Oh Snap, not again...
Thread Starter
 
atmdad's Avatar
 
Join Date: Mar 2010
Location: Cardiff, Ca
Posts: 608
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
0.1mm, that's asking alot from a crusty old veneir caliper in the hands of someone that has at times stopped complete strangers in a store to ask them to read the fine print on a label.

The post is just a generic "Laprade Type" from Harris Cyclery.

Originally Posted by jimmuller View Post

I wouldn't JB Weld the seatpost in place, if that's why you're asking.


That's a joke, I say, that's a joke, son.
atmdad is offline  
Old 10-20-11, 05:40 PM
  #13  
RobbieTunes
Banned
 
Join Date: Dec 2007
Posts: 27,297
Mentioned: 34 Post(s)
Tagged: 1 Thread(s)
Quoted: 378 Post(s)
Liked 1,372 Times in 886 Posts
Find a beer can collector, and get a steel one.
RobbieTunes is offline  
Old 10-20-11, 06:47 PM
  #14  
Paramount1973 
Senior Member
 
Paramount1973's Avatar
 
Join Date: Sep 2011
Location: The First State.
Posts: 1,165

Bikes: Schwinn Continental, Schwinn Paramount, Schwinn High Plains, Schwinn World Sport, Trek 420, Trek 930,Trek 660, Novara X-R, Giant Iguana. Fuji Sagres mixte.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 34 Post(s)
Liked 17 Times in 7 Posts
Don't use epoxy to glue in a shim, try a couple of drops of medium CA glue. The solvent is available from Woodcraft and elsewhere so it should be totally reversible.
Paramount1973 is offline  
Old 10-20-11, 07:10 PM
  #15  
Charles Wahl
Disraeli Gears
 
Charles Wahl's Avatar
 
Join Date: Jul 2007
Location: NYC
Posts: 3,933
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 370 Post(s)
Liked 187 Times in 122 Posts
I've had the experience that a Laprade 26.4 mm seat post bought for a project turned out to be just over 26.2, and just didn't work. The seat tube in question was thick enough that I had my LBS hone it out for a 26.6 mm post. Much happier, because I had an old Record 2-bolt post on hand in that size that's terrific.
Charles Wahl is offline  
Old 10-20-11, 09:21 PM
  #16  
illwafer
)) <> ((
 
illwafer's Avatar
 
Join Date: Mar 2008
Location: San Diego, CA
Posts: 2,412
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Liked 1 Time in 1 Post
atmdad,

if you got a 26.6 and need a 26.8, i'm your guy.
illwafer is offline  
Old 10-21-11, 04:26 AM
  #17  
old's'cool
curmudgineer
 
old's'cool's Avatar
 
Join Date: Dec 2009
Location: Chicago SW burbs
Posts: 4,365

Bikes: 2 many 2 fit here

Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 240 Post(s)
Liked 43 Times in 33 Posts
If you have access to a lathe and a knurling tool, you can judiciously knurl the part of the post that won't be exposed to the required dia. No disaster if the knurling goes too far up the post, except it won't look so hot exposed.
old's'cool is offline  
Old 10-21-11, 04:58 AM
  #18  
Road Fan
Senior Member
 
Road Fan's Avatar
 
Join Date: Apr 2005
Location: Ann Arbor, MI
Posts: 15,487

Bikes: 1980 Masi, 1984 Mondonico, 1984 Trek 610, 1980 Woodrup Giro, 2005 Mondonico Futura Leggera ELOS, 1967 PX10E, 1971 Peugeot UO-8

Mentioned: 42 Post(s)
Tagged: 0 Thread(s)
Quoted: 1295 Post(s)
Liked 254 Times in 206 Posts
I had this problem on my Trek 610, but the fitting error was much less - a 27.2 was too small, but a 27.4 was much too big. I shimmed it. I bought an assortment of brass shim at the local hardware store, and tried several thicknesses. The one that worked was (don't recall exactly) either .004 inch thickness or .006 inch thickness. It took several tries to get a shape and size that worked, and to learn how to install it (greased, all surfaces) so that the friction did not destroy the shim or bunch it. After a few installs it has a crease, but it's not a big problem.

f your discrepancy in size is "just a gnat's ass," a 1 or 2 mm shim will probably be much too thick.
Road Fan is offline  
Old 10-21-11, 06:36 AM
  #19  
rhm
multimodal commuter
 
rhm's Avatar
 
Join Date: Nov 2006
Location: NJ, NYC, LI
Posts: 19,641

Bikes: 1940s Fothergill, 1959 Allegro Special, 1963? Claud Butler Olympic Sprint, Lambert 'Clubman', 1974 Fuji "the Ace", 1976 Holdsworth 650b conversion rando bike, 1983 Trek 720 tourer, 1984 Counterpoint Opus II, 1993 Basso Gap, 2010 Downtube 8h, and...

Mentioned: 528 Post(s)
Tagged: 0 Thread(s)
Quoted: 1799 Post(s)
Liked 306 Times in 202 Posts
Oh, just shim it with a piece of a soda can. Not a beer can; canned beer sucks. Well, maybe one of those Guinness cans with the widget would be okay (discard the widget).
rhm is offline  
Old 10-21-11, 08:55 AM
  #20  
mparker326
Senior Member
 
mparker326's Avatar
 
Join Date: Aug 2006
Location: Knoxville, TN
Posts: 1,978

Bikes: Schwinn Paramount P15, Fisher Montare, Proteus, Rivendell Quickbeam

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Likes: 0
Liked 1 Time in 1 Post
Originally Posted by rhm View Post
Oh, just shim it with a piece of a soda can.
+1, I've done it numerous times and it works great.
mparker326 is offline  
Old 10-21-11, 09:15 AM
  #21  
Zaphod Beeblebrox 
PanGalacticGargleBlaster
 
Zaphod Beeblebrox's Avatar
 
Join Date: Apr 2009
Location: Smugglers Notch, Vermont
Posts: 7,536

Bikes: Upright and Recumbent....too many to list, mostly Vintage.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Likes: 0
Liked 3 Times in 2 Posts
just wanted to commiserate. I had the same problem with a Le Tour and with a World Voyageur.

I ended up buying a super cheapo seatpin and spending some quality time with it and some sandpaper.
__________________
--Don't Panic.
Zaphod Beeblebrox is offline  
Old 10-21-11, 09:47 AM
  #22  
atmdad
Oh Snap, not again...
Thread Starter
 
atmdad's Avatar
 
Join Date: Mar 2010
Location: Cardiff, Ca
Posts: 608
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Didn't mess with the seat post last night, just hung the drivetrain and got it all dialed in.

If any one is keeping a list, Vittoria Randonneurs are a pain in the ass to mount on Sun M13II rims.
atmdad is offline  
Old 10-21-11, 10:52 AM
  #23  
Zaphod Beeblebrox 
PanGalacticGargleBlaster
 
Zaphod Beeblebrox's Avatar
 
Join Date: Apr 2009
Location: Smugglers Notch, Vermont
Posts: 7,536

Bikes: Upright and Recumbent....too many to list, mostly Vintage.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Likes: 0
Liked 3 Times in 2 Posts
I've heard those rims are just difficult to mount tires to in general. I like the way they look though.
__________________
--Don't Panic.
Zaphod Beeblebrox is offline  
Old 10-21-11, 11:40 AM
  #24  
jimmuller 
What??? Only 2 wheels?
 
jimmuller's Avatar
 
Join Date: Apr 2010
Location: Boston-ish, MA
Posts: 13,337

Bikes: 73 Raleigh Carlton Gran Sport, 72 Peugeot UO-8, 82 Peugeot TH8, 87 Bianchi Brava, 76? Masi Grand Criterium, 87 Centurion Ironman Expert, 74 Motobecane Champion Team, 86 & 77 Gazelle champion mondial, 81? Grandis, 82? Tommasini, 83 Peugeot PF10

Mentioned: 183 Post(s)
Tagged: 0 Thread(s)
Quoted: 1190 Post(s)
Liked 288 Times in 145 Posts
Originally Posted by Zaphod Beeblebrox View Post
I've heard those rims are just difficult to mount tires to in general. I like the way they look though.
I have three of them on two bikes, all 27". I have no trouble putting Pasela TGs on them. Not hard at all. (The fourth rim is a Mavic MA2. So shoot me. It's on a French bike.)
__________________
Real cyclists use toe clips.
With great bikes comes great responsibility.
jimmuller
jimmuller is offline  
Old 10-21-11, 12:56 PM
  #25  
Zaphod Beeblebrox 
PanGalacticGargleBlaster
 
Zaphod Beeblebrox's Avatar
 
Join Date: Apr 2009
Location: Smugglers Notch, Vermont
Posts: 7,536

Bikes: Upright and Recumbent....too many to list, mostly Vintage.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Likes: 0
Liked 3 Times in 2 Posts
That's good news. I've always wanted a pair. It'd be nice if they did a run of em in 650B
__________________
--Don't Panic.
Zaphod Beeblebrox is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.