Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Solvers Seat Binder Bolt for steel frame size question

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Solvers Seat Binder Bolt for steel frame size question

Old 01-30-16, 04:45 PM
  #1  
tmh657
Senior Member
Thread Starter
 
tmh657's Avatar
 
Join Date: Aug 2008
Location: SoCal
Posts: 2,923

Bikes: A few BSO's.

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 162 Post(s)
Likes: 0
Liked 26 Times in 20 Posts
Seat Binder Bolt for steel frame size question

I snapped the seat post binder bolt so I will order a new one. This ad has them in 18,19 and 21mm sizes. I don't have anything to measure the existing broken bolt. It seems every one I have seen in my early 80's to mid 90's steel frame bike looks the same size. Is there a standard size or do I need to go to a shop with a micrometer? Hmmm, if I did that they might have the bolt in a drawer.

Problem Solvers Seat Binder Bolt > Components > Seatposts > Seatpost & Clamp Parts | Jenson USA

Last edited by tmh657; 01-30-16 at 04:52 PM.
tmh657 is offline  
Old 01-30-16, 04:58 PM
  #2  
HillRider
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,408

Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 1893 Post(s)
Likes: 0
Liked 872 Times in 616 Posts
Originally Posted by tmh657 View Post
I don't have anything to measure the existing broken bolt.
A metric ruler is very cheap and useful for a lot of things besides bikes. I recommend you get one.
HillRider is offline  
Old 01-30-16, 05:40 PM
  #3  
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,226

Bikes: Catrike 559 I own some others but they don't get ridden very much.

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1570 Post(s)
Liked 636 Times in 357 Posts
1. There are roughly 24.5 mm in an inch so the difference between 18 mm and 21 mm is only 1/8 inch. That's not very much.
2. If it didn't matter, Problem Solvers wouldn't have the binder bolts in 3 sizes that are so close together.

Bottom line, one accurate measurement is worth 1,000 assumptions. If you are planning to do very much work on bikes an accurate metric ruler is one of the best tool investments that you can make.
__________________
My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.
Retro Grouch is offline  
Likes For Retro Grouch:
Old 01-30-16, 07:06 PM
  #4  
tmh657
Senior Member
Thread Starter
 
tmh657's Avatar
 
Join Date: Aug 2008
Location: SoCal
Posts: 2,923

Bikes: A few BSO's.

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 162 Post(s)
Likes: 0
Liked 26 Times in 20 Posts
25.4mm= 1inch. So I didn't provide enough information in my question. Are the 3 lengths mentioned in the ad for the length of the bolt or the diameter? The website does not say. Measuring the length is simple, diameter not quite as easy to get it accurate.
tmh657 is offline  
Old 01-30-16, 07:23 PM
  #5  
Slash5
Senior Member
 
Join Date: Feb 2014
Location: Southern Ontario
Posts: 1,891
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 263 Post(s)
Likes: 0
Liked 7 Times in 6 Posts
Google "measure seat post bolt"
Found this:

The 19 refers to the measurement size of the bolt tightened completely as is, so it will go smaller than 21mm in order to tighten the seatpost. A 22mm will not tighten down because it can't go smaller than 22mm.
Slash5 is offline  
Old 01-30-16, 08:15 PM
  #6  
tmh657
Senior Member
Thread Starter
 
tmh657's Avatar
 
Join Date: Aug 2008
Location: SoCal
Posts: 2,923

Bikes: A few BSO's.

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 162 Post(s)
Likes: 0
Liked 26 Times in 20 Posts
Originally Posted by Slash5 View Post
Google "measure seat post bolt"
Found this:

The 19 refers to the measurement size of the bolt tightened completely as is, so it will go smaller than 21mm in order to tighten the seatpost. A 22mm will not tighten down because it can't go smaller than 22mm.

Got it, thanks.
tmh657 is offline  
Old 01-30-16, 08:32 PM
  #7  
Bike tinker man
Senior Member
 
Join Date: Dec 2014
Location: Retired to Penang Malaysia originally from UK
Posts: 344

Bikes: My 1978 Raleigh from new, 1995 Trek, & constant changing & rebuilding of other bike projects.

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 41 Post(s)
Likes: 0
Liked 3 Times in 3 Posts
The diameter of the bolts should all be the same, the bolt head has a spigot / line up so it does not turn, on the nut end there is a SS flat washer to help in even clamp force out, & stop scratching the paintwork, if the bolt is too long obviously no clamp force, as mentioned above you really need to measure with a simple cheap steel ruler what lenght you have, remembering its possibly fully compressed now if you sheared the present thread, if the bolt is too long when you buy & try it, then you can always add another washer as a fix.
Bike tinker man is offline  
Old 01-30-16, 11:55 PM
  #8  
CycleryNorth81
Senior Member
 
Join Date: Jun 2014
Posts: 877

Bikes: custom Cyclery North (Chicago), Schwinn Circuit

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 350 Post(s)
Liked 202 Times in 117 Posts
Originally Posted by tmh657 View Post
I snapped the seat post binder bolt so I will order a new one. This ad has them in 18,19 and 21mm sizes. I don't have anything to measure the existing broken bolt. It seems every one I have seen in my early 80's to mid 90's steel frame bike looks the same size. Is there a standard size or do I need to go to a shop with a micrometer? Hmmm, if I did that they might have the bolt in a drawer.

Problem Solvers Seat Binder Bolt > Components > Seatposts > Seatpost & Clamp Parts | Jenson USA

The numbers (18,19, 21) refer to the length of the bolt. The length of the bolt is measured within the two inner face of the bolt.
CycleryNorth81 is offline  
Old 06-10-22, 05:26 PM
  #9  
Mr.Wonderful
Junior Member
 
Join Date: Feb 2022
Location: Jamesville, NY
Posts: 11

Bikes: Trek Allant +7S

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked 0 Times in 0 Posts
Thank you for this post. This helped me solve my problem too.

I want to ask a further question:Regarding "the bolt head has a spigot / line up so it does not turn," on my 30 year old bike I noticed the area where the spigot goes in (on the seat tube) has worn out a bit because I never knew about the spigot on the bolt head until today. It still is ok and it does not turn but if this was totally worn out, are there other options to prevent the seat from collapsing into the tube? Can one put a bolt and nut to just tighten it (not good cosmetically) and use something else to keep the seat from moving?

Thank you.
Mr.Wonderful is offline  
Old 06-10-22, 06:07 PM
  #10  
jccaclimber
Senior Member
 
Join Date: May 2005
Location: SFBay
Posts: 2,290

Bikes: n, I would like n+1

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 113 Post(s)
Likes: 0
Liked 114 Times in 92 Posts
A little wear where the rib goes doesnít matter, itís just there so the bolt doesnít spin. Some seatpost bolts have a hex opening in both sides, so itís even less necessary. Also note, Campy seatpost bolts donít have that rib, so a bike designed for them wonít even have the slot. I only know that as my 80ís Davidson is that way. When I got it it had a normal seatpost bolt and several washers jammed in there. At some point someone pointed the issue out to me, and of course the Campy bolt (also a bit shorter) fit perfectly.
jccaclimber is offline  
Likes For jccaclimber:
Old 06-10-22, 06:13 PM
  #11  
Mr.Wonderful
Junior Member
 
Join Date: Feb 2022
Location: Jamesville, NY
Posts: 11

Bikes: Trek Allant +7S

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked 0 Times in 0 Posts
Originally Posted by jccaclimber View Post
A little wear where the rib goes doesnít matter, itís just there so the bolt doesnít spin. Some seatpost bolts have a hex opening in both sides, so itís even less necessary. Also note, Campy seatpost bolts donít have that rib, so a bike designed for them wonít even have the slot. I only know that as my 80ís Davidson is that way. When I got it it had a normal seatpost bolt and several washers jammed in there. At some point someone pointed the issue out to me, and of course the Campy bolt (also a bit shorter) fit perfectly.
Thank you. Appreciate it.
Mr.Wonderful is offline  
Old 06-11-22, 08:43 AM
  #12  
tkamd73 
Senior Member
 
Join Date: Dec 2015
Location: Menomonee Falls, WI
Posts: 1,624

Bikes: 1984 Schwinn Supersport, 1988 Trek 400T, 1977 Trek TX900, 1982 Bianchi Champione del Mondo, 1978 Raleigh Supercourse, 1986 Trek 400 Elance, 1991 Waterford PDG OS Paramount, 1971 Schwinn Sports Tourer, 1985 Trek 670

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 531 Post(s)
Liked 774 Times in 417 Posts
Had a similar situation recently, early 90s Tange Prestige road bike frame. Needing a replacement, I found this on Amazon, which took some of the guesswork out, got it quick, much nicer then the original, and cheap enough to just buy all 3 if you donít feel like measuring. Higher end road bike frame, 19mm will probably work.
Tim


tkamd73 is offline  
Old 06-11-22, 09:19 AM
  #13  
Mr.Wonderful
Junior Member
 
Join Date: Feb 2022
Location: Jamesville, NY
Posts: 11

Bikes: Trek Allant +7S

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked 0 Times in 0 Posts
Thank you. I saw that too.

Maybe this will work too. Or maybe one of these might be easier.
Mr.Wonderful is offline  
Old 06-14-22, 11:57 AM
  #14  
CyclingFool95 
Full Member
 
Join Date: Apr 2019
Location: Northern NJ
Posts: 404

Bikes: 1987 Pinarello Montello, 1996 Litespeed Classic, 1996 Colnago Master Light, 1997 Litespeed Ultimate, 2006 Opera Leonardo FP, 2006 Pinarello Paris FP, 1984 Pinarello Record, 89-ish Cornelo Profilo

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 142 Post(s)
Liked 93 Times in 67 Posts
Originally Posted by tkamd73 View Post
Had a similar situation recently, early 90s Tange Prestige road bike frame. Needing a replacement, I found this on Amazon, which took some of the guesswork out, got it quick, much nicer then the original, and cheap enough to just buy all 3 if you donít feel like measuring. Higher end road bike frame, 19mm will probably work.
Tim


I just put the 19mm into a Series 7 PDG. Seems good. Hope it doesn't snap under load.
CyclingFool95 is offline  
Old 06-14-22, 01:34 PM
  #15  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 16,593

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Srewart 650B ATB

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3577 Post(s)
Liked 2,435 Times in 1,546 Posts
Not yet mentioned is why the old bolt broke. This info might be nice to know to possibly avoid the replacement from breaking too.

A common contribution is that the seat binder barrel/collar/lug ears become stretched and their end faces end up being longer are parallel to each other. The result is that as you tighten the bolt it's shoulders try to stay flush against the angling faces of the binder. This places a bend in the bolt and as you turn it to tighten this bend is changing, think about bending a paperclip wire till it fractures.

A common reason why the binder stretches is that a too small a post was used and/or poor finishing of the seat tube ID.

Back to which bolt is best. I have found that while a measurement is worth a thousand assumptions, a trial fit is worth a thousand measurements This is a classic reason to visit a LBS and size the bolt before you buy. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Old 06-14-22, 04:37 PM
  #16  
tkamd73 
Senior Member
 
Join Date: Dec 2015
Location: Menomonee Falls, WI
Posts: 1,624

Bikes: 1984 Schwinn Supersport, 1988 Trek 400T, 1977 Trek TX900, 1982 Bianchi Champione del Mondo, 1978 Raleigh Supercourse, 1986 Trek 400 Elance, 1991 Waterford PDG OS Paramount, 1971 Schwinn Sports Tourer, 1985 Trek 670

Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 531 Post(s)
Liked 774 Times in 417 Posts
Originally Posted by CyclingFool95 View Post
I just put the 19mm into a Series 7 PDG. Seems good. Hope it doesn't snap under load.
installed the 19mm binder bolt on a series 5 PDG frame, same frame as yours, great fit, I doubt you will have any issues.
Tim
tkamd73 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
gearbasher
Classic & Vintage
18
12-26-20 03:37 AM
littlebeetle
Classic & Vintage
7
12-24-13 11:45 AM
CanadianBiker32
Bicycle Mechanics
6
06-01-13 10:34 PM
marleyisdead
Bicycle Mechanics
5
02-12-13 06:55 PM
Ridefreemc
Folding Bikes
10
07-06-12 04:54 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


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.