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

Looks like a Square Taper ! But is not !

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.

Looks like a Square Taper ! But is not !

Old 01-27-22, 09:46 PM
  #1  
atlantis
Senior Member
Thread Starter
 
Join Date: Jun 2011
Posts: 94
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Looks like a Square Taper ! But is not !

Hi !
Can you please help me identify this particular bb ?
Its a scott entry level hybrid not too old components eg. Tektro Hydraulics, shimano 8 speed trigger shifters , 3x8 drivetrain.
There was some play in the bb hence decided to open her up.
The cups did not turn easy even with a cheater bar , assumption was sq taper bbs are tough to open. However when opened the cups seemed to fitted down with some grey threadlock.
Findlings
1. Both the cups were made of plastic.
2. The cups did not have thread throughout, seemed more like caps on an air tight jar.
3. The Nds cup opened up but was unable to remove the Ds cup since there was a retention washer on the spindle.
4 . On close observation observed that cartridges had directly been pressed into the frame way inside and there is no single piece cartridge.
Could you please assist me in identifying this bb, cause I fear, if I force the bearing out , I might not be able to thread a sq taper bb.
The dimensions of the current bb is 68x120
Looking forward to your replies

ps: the ripped threads you see in one of the images are of the plastic cup, not the shell.

Nds

Drive side not op enable

Nds after cleaning

Drive side
atlantis is offline  
Old 01-27-22, 10:11 PM
  #2  
cxwrench
Senior Member
 
cxwrench's Avatar
 
Join Date: Jul 2013
Location: Nor-Cal
Posts: 3,068

Bikes: lots

Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 1517 Post(s)
Liked 2,177 Times in 1,134 Posts
Looks like a normal Shimano cartridge bb to me. The only other thing I have to offer is that you take terrible photos.
cxwrench is offline  
Likes For cxwrench:
Old 01-27-22, 10:19 PM
  #3  
SalsaShark
Senior Member
 
SalsaShark's Avatar
 
Join Date: Nov 2014
Location: Eastern Iowa
Posts: 594

Bikes: 2014 Trek Allant drop bar conversion, modified Schwinn MTN commuter, 2015 Trek 520, Soma ES, Salsa Journeyman, 1980 Trek 414

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 159 Post(s)
Liked 314 Times in 152 Posts
This looks like a common OEM cartridge style square taper bottom bracket. They are not designed to be serviced. You look to have somehow destroyed yours and will likely have a difficult time removing the cartridge from the BB shell. Did you perhaps have such trouble turning the 'cups' because you were turning in the wrong direction for removal? Standard English threading on this frame would apply, and the NDS retaining cup would be removed first (turning counterclockwise). The drive side would then be turned clockwise to remove the cartridge. If you turned the wrong direction with enough force, you could snap the installation retaining cups, and be left with a cartridge still threaded in place in the shell. This looks like what you have ended up with.
The BB spindle was indeed square tapered, regardless of your experience with other bottom bracket designs. A square taper spindle can be part of a loose ball system, or a cartridge system. As for removal of the assembly, if you have indeed severed the cups through the threading, you are going to have to find a way to turn the outer housing clockwise out of the BB shell when viewed from the drive-side. Maybe a strategically placed punch and a hammer can get it rotating. Perhaps another member has encountered this and will have a better idea.
SalsaShark is offline  
Likes For SalsaShark:
Old 01-27-22, 10:39 PM
  #4  
TPL
Senior Member
 
Join Date: Jul 2017
Posts: 248
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 142 Post(s)
Likes: 0
Liked 88 Times in 63 Posts
Lesson to be learned here ...

NOT everything on a bicycle is a co9nventional right hand thread

Get thee to a bicycle dealer !
TPL is offline  
Likes For TPL:
Old 01-27-22, 11:24 PM
  #5  
zandoval 
Senior Member
 
zandoval's Avatar
 
Join Date: May 2010
Location: Bastrop Texas
Posts: 3,129

Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 453 Post(s)
Liked 662 Times in 443 Posts
We live and we learn and the Forum helps... Allot...

Man... How many times have I screwed up tinkering around on my bikes? Luckily all have survived... My tinkering... HA

As for bicycle dealers... It's a thought but... No...

Now that ya know what you've got I am sure you will figure it out. If your threads are buggered bad you can always go to a Threadless Bottom Bracket Repair Cartridge. They are not that much more in cost than a regular unit. There are plenty of Youtubes on how to install a Threadless Repair Unit.
__________________
No matter where your at... There you are... Δf:=f(1/2)-f(-1/2)

Last edited by zandoval; 01-27-22 at 11:30 PM.
zandoval is offline  
Old 01-28-22, 08:49 AM
  #6  
mitchmellow62
Senior Member
 
Join Date: Aug 2014
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 64 Post(s)
Liked 38 Times in 29 Posts
I too think you have a sealed bearing cartridge. However, it may not be like a shimano. There have been a number of styles. For example, the Phil Wood had threaded "mounting rings"(shimano calls them adaptors) on both sides and the cartridge itself was unthreaded. Take a look at this article for info: https://www.sheldonbrown.com/tooltips/cartridge.html . I believe the sequence of your photo's from top to bottom is: drive side, non-drive side, drive side, non-drive side. Clearly, the drive side shows a mounting ring/adaptor which would eliminate it from being Shimano. In the bottom photo I believe I see the face of the bottom bracket shell and internal threading (that may be damaged depending on what the wire like item is). Was there also a mounting ring/adaptor that you removed? If the answer is yes and you have removed the mounting ring/adaptor from the drive side then the cartridge should pop out with a little force. Being cautious and not too forceful I'd give it a rap and see if it loosens. If there was no threaded mounting ring/adaptor on the drive side then I'm a little lost although clearly that is a sealed bearing we are looking at in the photo. Hope that helps. If the threads have been damaged remember Zandoval's recommendation. Good luck.
mitchmellow62 is offline  
Old 01-28-22, 08:53 AM
  #7  
mitchmellow62
Senior Member
 
Join Date: Aug 2014
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 64 Post(s)
Liked 38 Times in 29 Posts
Correction: 5 photos in NDS, DS, NDS, DS, NDS sequence.
mitchmellow62 is offline  
Old 01-28-22, 09:44 AM
  #8  
dedhed
SE Wis
 
dedhed's Avatar
 
Join Date: Apr 2005
Location: Milwaukee, WI
Posts: 8,939

Bikes: '68 Raleigh Sprite, '02 Raleigh C500, '84 Raleigh Gran Prix, '91 Trek 400, 2013 Novara Randonee, 1990 Trek 970

Mentioned: 32 Post(s)
Tagged: 0 Thread(s)
Quoted: 2098 Post(s)
Liked 2,090 Times in 1,290 Posts
Looks like the DS cup is out. Should be able to tap from the NDS to get the cartridge out. That'll give you room to play around on the NDS to get the rest of the broken NDS plastic cup out. Think picks, blades, etc to try to unthread it as well as some heat to soften it up. Most likely it'll be a destructive removal. I'd have the threads chased before installing a replacement.
dedhed is offline  
Likes For dedhed:
Old 01-28-22, 10:16 AM
  #9  
atlantis
Senior Member
Thread Starter
 
Join Date: Jun 2011
Posts: 94
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Apologies for the terrible photos, they were not meant to be posted, only for my reference. Then it struck me last night that I should get in touch with you all. Its been ages since I have posted.....
Anyway just for a bit more info, I have successfully opened square taper bbs, likes of shimano un26, the older un54, and some VP bbs and Chin Haur. The thread direction is something I am well versed with.
My query was, this is not something that I have seen before, these cartridges are individually fixed inside, not at the lip of the bb shell. And the outer covers/cups are too flimsy on both the Ds and Nds. Unlike the square tapers that I have worked with, where the Ds cartridge is fixed to the cup.
Even if the Bb is destroyed inside and got stuck or what ever, the semblance of its default design does not exist.
The threads(the wire like item) that you see in the image or flattened portion at the head of the bb shell is actually the plastic from the cups as well the threadlock used and not a sign of damaged Bb shell threads.
Thanks for you inputs , I just felt some member would have come across this particular design........
atlantis is offline  
Old 01-28-22, 10:59 AM
  #10  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,065

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 1486 Post(s)
Liked 744 Times in 546 Posts
Originally Posted by atlantis View Post
Apologies for the terrible photos, they were not meant to be posted, only for my reference. Then it struck me last night that I should get in touch with you all. Its been ages since I have posted.....
Anyway just for a bit more info, I have successfully opened square taper bbs, likes of shimano un26, the older un54, and some VP bbs and Chin Haur. The thread direction is something I am well versed with.
My query was, this is not something that I have seen before, these cartridges are individually fixed inside, not at the lip of the bb shell. And the outer covers/cups are too flimsy on both the Ds and Nds. Unlike the square tapers that I have worked with, where the Ds cartridge is fixed to the cup.
Even if the Bb is destroyed inside and got stuck or what ever, the semblance of its default design does not exist.
The threads(the wire like item) that you see in the image or flattened portion at the head of the bb shell is actually the plastic from the cups as well the threadlock used and not a sign of damaged Bb shell threads.
Thanks for you inputs , I just felt some member would have come across this particular design........
In pic #2, D-NL SCREAMS SHIMANO
It's a conventional cartridge BB (probably a UN-26 quality) with the DS flange sheared off.
Bill Kapaun is offline  
Likes For Bill Kapaun:
Old 01-28-22, 02:15 PM
  #11  
bboy314
Senior Member
 
bboy314's Avatar
 
Join Date: Dec 2008
Location: Pioneer Valley
Posts: 332
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 72 Post(s)
Liked 124 Times in 73 Posts
https://bike.shimano.com/en-EU/produ.../BB-UN100.html

I wonder if itís one of these - I came across one for the first time recently. Was surprised to see plastic cups on both sides.
bboy314 is offline  
Old 01-29-22, 07:18 AM
  #12  
mitchmellow62
Senior Member
 
Join Date: Aug 2014
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 64 Post(s)
Liked 38 Times in 29 Posts
Originally Posted by bboy314 View Post
https://bike.shimano.com/en-EU/produ.../BB-UN100.html

I wonder if itís one of these - I came across one for the first time recently. Was surprised to see plastic cups on both sides.
It doesn't appear to be if you look at this schematic: https://si.shimano.com/api/publish/s...UN100-3834.pdf
mitchmellow62 is offline  
Old 01-29-22, 07:37 AM
  #13  
Moe Zhoost
Half way there
 
Moe Zhoost's Avatar
 
Join Date: Sep 2015
Location: North Carolina
Posts: 2,657

Bikes: Many, and the list changes frequently

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 882 Post(s)
Liked 682 Times in 412 Posts
Originally Posted by Bill Kapaun View Post
In pic #2, D-NL SCREAMS SHIMANO
It's a conventional cartridge BB (probably a UN-26 quality) with the DS flange sheared off.
I've never seen a DS flange sheared off, but I reckon it's possible, especially if made of plastic. It could have been like this since installation, though I'd assume that it would have loosened up before.

My suggestion is to first give it a few wacks with a mallet on the NDS to drive the cartridge out the way it was installed. Another idea would be to reinstall the cranks and ride it around a bit to see if that frees things up.

Good luck and let us know what happens
Moe Zhoost is offline  

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.