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

Knocking in bike hub? May be ground up ball bearings!

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.

Knocking in bike hub? May be ground up ball bearings!

Old 09-24-14, 06:03 PM
  #1  
Adnan
Junior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Knocking in bike hub? May be ground up ball bearings!

So I had someone tell me their hub was making a knocking sound coming from their front hub as they rode. So I opened it up to do an overhaul, expecting to find some debris or a loose bearing in the hub shell but surprisingly i found ground down and misshapen ball bearings! On one side, there were the 11 damaged balls, and on the other there were 8 bearings instead of 11.
I cleaned out the old grease and there were metal shavings and powder all over the cloth. Thankfully the cups and cones weren't pitted, so I just had to put in new bearings.
Heres a picture, pretty crazy huh?

Attached Images
File Type: jpg
IMG_4606.jpg (88.3 KB, 47 views)
Adnan is offline  
Old 09-24-14, 06:10 PM
  #2  
fietsbob
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,599

Bikes: 8

Mentioned: 197 Post(s)
Tagged: 0 Thread(s)
Quoted: 7607 Post(s)
Liked 1,322 Times in 832 Posts
Someone waited a bit to long .. I always toss the balls ..then put new ones in fresh grease..
fietsbob is offline  
Old 09-24-14, 06:24 PM
  #3  
headloss 
Lost at sea...
 
headloss's Avatar
 
Join Date: Dec 2012
Location: Western PA
Posts: 935

Bikes: Schwinn Paramount (match), Trek 520, random bits and pieces...

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Waited too long? Looks/sounds like there weren't enough bearings to begin with caused the rest to deteriorate. That's crazy that the cup/cone surfaces survived that. The only time I've seen something like that was when I pulled off a cheap non-cartridge square taper BB on a big box bike.
headloss is offline  
Old 09-24-14, 09:55 PM
  #4  
FBinNY
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 35,964

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 125 Post(s)
Tagged: 1 Thread(s)
Quoted: 4368 Post(s)
Likes: 0
Liked 40 Times in 35 Posts
Originally Posted by headloss View Post
Waited too long? Looks/sounds like there weren't enough bearings to begin with caused the rest to deteriorate....
Being a few balls short of a set probably wouldn't cause the issue, or would have been apparent early on. If this was an older hub with lots of time and miles since the last service, I suspect that it started out with a full complement on both sides, and lost three to fracturing (those metal fragments are the remains of the missing balls).

Some time along the way, probably not that long before the owner noticed the problem one ball broke or chipped, possibly from running into a grain of sand. That left shrapnel in the bearing leading to the failures of others. Remember that a ball bearing runs with zero clearance and the balls in constant contact with both races. So if anything is on the track, the ball cannot climb over it. It must either push it out of the way or crush it. Some things don't crush easily so the balls chip or fracture putting even more crap into the track.
FBinNY is offline  
Old 09-25-14, 08:47 AM
  #5  
headloss 
Lost at sea...
 
headloss's Avatar
 
Join Date: Dec 2012
Location: Western PA
Posts: 935

Bikes: Schwinn Paramount (match), Trek 520, random bits and pieces...

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by FBinNY View Post
Being a few balls short of a set probably wouldn't cause the issue, or would have been apparent early on. If this was an older hub with lots of time and miles since the last service, I suspect that it started out with a full complement on both sides, and lost three to fracturing (those metal fragments are the remains of the missing balls).

Some time along the way, probably not that long before the owner noticed the problem one ball broke or chipped, possibly from running into a grain of sand. That left shrapnel in the bearing leading to the failures of others. Remember that a ball bearing runs with zero clearance and the balls in constant contact with both races. So if anything is on the track, the ball cannot climb over it. It must either push it out of the way or crush it. Some things don't crush easily so the balls chip or fracture putting even more crap into the track.
I'm just having a hard time believing that the races were OK after that type of bearing-ball failure. Perhaps you're right... I'm goofy enough that I'd let the metal settle out from the grease and I'd weigh the fragments to confirm. I see your point, regarding a cascading effect, but that's still a crazy failure. It just seems to me that if it was due to miles/time and the grease went bad that there would be pitting or some other signs of damage to the cups/cones as opposed to the damage being restricted to the balls.

Whatever the case, weird. Thanks @Adnan for sharing.
headloss is offline  
Old 09-27-14, 11:39 AM
  #6  
Adnan
Junior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Yeah that sounded logical to me too, but the weird thing is that the shavings were only on the side with the full set. The grease was clean on the side with 3 short.
Adnan is offline  
Old 09-27-14, 11:42 AM
  #7  
Adnan
Junior Member
Thread Starter
 
Join Date: Aug 2014
Posts: 12
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
And yeah the fragmenting bearings cycle is probably what happened if something got its way in there. I guess the cups and cones are just made of harder metal so that the bearings fail first. Good thing, because ball bearings are much easier to find than cup/cones!
Adnan is offline  
Old 09-27-14, 03:31 PM
  #8  
noglider 
aka Tom Reingold
 
noglider's Avatar
 
Join Date: Jan 2009
Location: High Falls, NY, USA
Posts: 39,989

Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem

Mentioned: 486 Post(s)
Tagged: 0 Thread(s)
Quoted: 6909 Post(s)
Liked 1,566 Times in 991 Posts
I have seen stuff this crazy and crazier. Now that @FNinNY explains it, I understand it. I've seen ruined balls with intact races, and I have seen the opposite. Stuff happens!
__________________
Tom Reingold, tom@noglider.com
New York City and High Falls, NY
Blogs: The Experienced Cyclist; noglider's ride blog

“When man invented the bicycle he reached the peak of his attainments.” — Elizabeth West, US author

Please email me rather than PM'ing me. Thanks.
noglider is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
richard4993
Bicycle Mechanics
3
01-31-16 06:30 PM
oldbicycles
Classic & Vintage
9
11-22-15 06:55 PM
RT Metro
Bicycle Mechanics
13
03-07-12 10:19 AM
Amesja
Classic & Vintage
30
03-22-11 06:44 AM
shubonker
Bicycle Mechanics
5
06-24-10 04:03 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.