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

Cross threading. Darn it.

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.

Cross threading. Darn it.

Old 01-21-19, 12:26 PM
  #1  
MiloFrance 
Not riding enough
Thread Starter
 
MiloFrance's Avatar
 
Join Date: Aug 2014
Location: Capestang, France
Posts: 1,186

Bikes: Lots of French, some British and a couple of Italian

Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 179 Post(s)
Liked 14 Times in 12 Posts
Cross threading. Darn it.

Hi all. I bought an after market French threaded BB for a steel frame. It arrived, I lined it up and gently started to ease it in (fixed side). It almost immediately went sideways with very little pressure. Taking it out I was a bit surprised that the alloy was so soft that it had been damaged by so little at the start of the thread. Using a needle file I took the damaged bit off and tried again. No matter what I do, it won't go. It is the correct thread, I've done many of them before and all the threads are clean
Any other suggestions please?
Cheers
Milo
__________________
I'm on holiday whenever I ride my bike
MiloFrance is offline  
Old 01-21-19, 12:42 PM
  #2  
Bill Kapaun
Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 10,958

Bikes: 86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 729 Post(s)
Liked 59 Times in 47 Posts
Are you turning it backwards until you feel a thread "drop in" before screwing it in?
Bill Kapaun is offline  
Old 01-21-19, 12:58 PM
  #3  
CliffordK
Senior Member
 
CliffordK's Avatar
 
Join Date: Nov 2014
Location: Eugene, Oregon, USA
Posts: 22,951
Mentioned: 178 Post(s)
Tagged: 0 Thread(s)
Quoted: 9168 Post(s)
Liked 194 Times in 155 Posts
You're sure it is French, right? And, you have the right/left threading correct. Swiss?

You might hunt down some steel cups that you could try first, before you tear up your aluminum cups any more.
CliffordK is online now  
Old 01-21-19, 01:36 PM
  #4  
3alarmer
******
 
3alarmer's Avatar
 
Join Date: Nov 2010
Location: The Big Tomato
Posts: 17,562

Bikes: old ones

Mentioned: 242 Post(s)
Tagged: 0 Thread(s)
Quoted: 15329 Post(s)
Liked 224 Times in 194 Posts
...sometimes it helps if you put in the non fixed cup first, and screw it in just a few turns (not all the way). This gives you a smaller hole for the spindle to exit on that side, which in turn helps to straighten and center the sealed unit with the fixed cup that is integral to it. Then youi do the backward turning until you feel a little click business, and you should be OK. Anyway, that's how I do them.
3alarmer is offline  
Old 01-21-19, 01:45 PM
  #5  
stevoo
Stevoo
 
Join Date: Jun 2013
Location: So Cal
Posts: 200

Bikes: Road and mountain tandems, single bikes too.

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 29 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Have found over the years that some manufacturers just cannot hold tolerances very well. Had some bottom brackets that just has threads a tad oversize. Very frustrating but it happens.
Example:
Carefully chased frame with proper taps. Nice n clean and lubed.
Had several brand new BB's in the shop.
Some were quite a loose fit and even rattled a bit until torqued. Some were very good fit. Some were kind of snug by hand. One brand was super tight. One brand just would not go in.

Bottom line is that it seems thread quality can be all over the place.

Good luck.
stevoo is offline  
Old 01-24-19, 03:21 PM
  #6  
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 29,386

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

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 1214 Post(s)
Liked 67 Times in 52 Posts
Do you happen to have an under the bottom bracket cable guide? If you haven't already done it, I'd check for a screw or something similar hitting the bottom bracket as you try to install it.
__________________
My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.
Retro Grouch is offline  
Old 01-24-19, 03:54 PM
  #7  
hokiefyd
Senior Member
 
Join Date: Feb 2017
Location: Northern Shenandoah Valley
Posts: 2,457

Bikes: 2018 Redline Zander, 2018 Giant Roam 2, 1997 Trek 750, 1981 Peugeot PBN10, 1970 Peugeot UO-18

Mentioned: 28 Post(s)
Tagged: 0 Thread(s)
Quoted: 846 Post(s)
Liked 103 Times in 83 Posts
Originally Posted by 3alarmer View Post
...sometimes it helps if you put in the non fixed cup first, and screw it in just a few turns (not all the way). This gives you a smaller hole for the spindle to exit on that side, which in turn helps to straighten and center the sealed unit with the fixed cup that is integral to it. Then youi do the backward turning until you feel a little click business, and you should be OK. Anyway, that's how I do them.
This is exactly what I do for two-piece cartridge bearings, where you have a cartridge assembly and then a non drive side "cup" as a retainer.

But I join @CliffordK in asking if you know in absolute certainty that it's French-threaded. Swiss threads use the 35x1mm French threads, but the drive side is left hand thread (like English and others) rather than the French's right hand thread.
hokiefyd is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
rhm
Classic & Vintage
20
12-24-16 08:03 AM
greg3rd48
Classic & Vintage
32
04-29-16 11:47 AM
pstock
Bicycle Mechanics
3
04-11-14 09:28 AM
scale
Classic & Vintage
15
05-24-11 12:48 PM
HappyHumber
Bicycle Mechanics
10
12-23-10 08:02 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

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.