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

Bottecchia Seat Tube Issue?

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.

Bottecchia Seat Tube Issue?

Old 01-06-18, 03:25 PM
  #1  
Senior Member
Thread Starter
 
crandress's Avatar
 
Join Date: Feb 2013
Location: Lexington, KY
Posts: 1,219

Bikes: 1980 Mercian Vincitore, Bridgestone MB3, Atala Corsa GS, Bottecchia Gran Turismo, 1953 Terrot

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 333 Post(s)
Liked 52 Times in 36 Posts
Bottecchia Seat Tube Issue?

I finally got the seat post out of my Bottecchia and could see a little lip protruding from the tip seat tube lug. I assume this is the seat tube. Is this indicative of an issue or just slight misalignment between the lug and seat tube? Maybe this is normal and I never noticed on my other bikes.

Also, the seat post was shockingly long. What should be the normal length of a seat post on a smallish road frame? This on was 193mm above the minimum insertion line.

What is your assessment? Thanks in advance.

IMG_5581 by Christopher Andress, on Flickr

IMG_5579 by Christopher Andress, on Flickr
__________________
Chris

Crapmaster Emeritus

Last edited by crandress; 01-06-18 at 03:30 PM.
crandress is offline  
Old 01-06-18, 03:48 PM
  #2  
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Posts: 24,840

Bikes: Several, mostly not name brands.

Mentioned: 154 Post(s)
Tagged: 0 Thread(s)
Quoted: 3617 Post(s)
Liked 3,448 Times in 1,958 Posts
Could be a shim. Can you see a lower edge inside the seat tube?
JohnDThompson is offline  
Old 01-06-18, 04:02 PM
  #3  
Decrepit Member
 
Scooper's Avatar
 
Join Date: Aug 2005
Location: Santa Rosa, California
Posts: 10,488

Bikes: Waterford 953 RS-22, several Paramounts

Mentioned: 72 Post(s)
Tagged: 0 Thread(s)
Quoted: 634 Post(s)
Liked 70 Times in 58 Posts
Chris, the quick way to tell if it's just the seat tube not cut flush with the top of the seat lug is to use a caliper to measure the seat tube below the seat lug and that short extension above the seat lug. If the O.D. is the same, it's just the seat tube not flush with the top of the seat lug.

The weight of the rider is a consideration in having a lot of seatpost showing above the seat lug since the bending moment is greater the greater the length of the seatpost between the lug and the saddle. If there's a lot of seatpost showing (more than six or eight inches) to get a reasonable fit on a small frame, get a bigger frame.
__________________
- Stan

my bikes

Science doesn't care what you believe.
Scooper is offline  
Old 01-06-18, 05:03 PM
  #4  
Senior Member
Thread Starter
 
crandress's Avatar
 
Join Date: Feb 2013
Location: Lexington, KY
Posts: 1,219

Bikes: 1980 Mercian Vincitore, Bridgestone MB3, Atala Corsa GS, Bottecchia Gran Turismo, 1953 Terrot

Mentioned: 49 Post(s)
Tagged: 0 Thread(s)
Quoted: 333 Post(s)
Liked 52 Times in 36 Posts
Thanks guys. Sorry, I had measured and yes, the tube is the same diameter above as below the lug. And there certainly is no insert. That is what I thought originally. I was wondering if it was indicative of a failing lug. Or if this not uncommon. Nothing seems loose or wiggly.

As far as the seat post, I certainly do NOT need an extensive amount of seat post. In fact the bike is probably a touch big, so I need less. Seems like an excessively long seat post since most of it is inside the tube. Even when I purchased it was not too high. I was shocked at how much seat post was inside.

Unless anyone else has a different take, I assume this is just normal and there is no problem riding as is. The seat post I am certain is too long, I can use it, but will look for a shorter one. It is a smaller diameter than any of the ones I have at 26.2mm. Funny, the Atala I just bought has the same diameter and I plan to get a new seat post for that one too. So I will be on the lookout for two. Seems Campy did not make too many of that size, which would be my preference. We will see what I can find at the Madison bike swap next week. Maybe I will get lucky!
__________________
Chris

Crapmaster Emeritus
crandress is offline  
Old 01-06-18, 05:56 PM
  #5  
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Posts: 24,840

Bikes: Several, mostly not name brands.

Mentioned: 154 Post(s)
Tagged: 0 Thread(s)
Quoted: 3617 Post(s)
Liked 3,448 Times in 1,958 Posts
Originally Posted by crandress
Thanks guys. Sorry, I had measured and yes, the tube is the same diameter above as below the lug. And there certainly is no insert. That is what I thought originally. I was wondering if it was indicative of a failing lug.
If it's not a shim, it probably just means the seat tube was trimmed slightly above the top of the seat lug. In most cases, the builder would file it down flush, so it doesn't project, but it's not a a structural concern. It just looks unfinished.
JohnDThompson is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Just Riding
Bicycle Mechanics
14
11-16-22 11:50 AM
TiHabanero
Framebuilders
5
06-19-19 06:58 PM
cpsqlrwn
Classic & Vintage
14
04-26-16 11:12 AM
Peyote
Bicycle Mechanics
21
07-29-12 02:40 PM
fauxto nick
Road Cycling
2
01-22-12 11:35 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.