FatCogs Community Discussion Forums

Go Back   FatCogs Community Discussion Forums > Fat Chance Bicycles > General Fat Chance Discussion

General Fat Chance Discussion Anything and everything about the best mountain bikes ever made.

Reply
 
Thread Tools Search this Thread Display Modes
Old October 4th, 2011, 12:55 PM   #1
mkozaczek
Senior Member
 
Join Date: August 11th, 2011
Location: Los Angeles, CA
Posts: 121
Default Removing FAT BB

So, one of my Yos has a completely dead factory BB.

My idea of how to remove the BB is as follows

1. Remove collars from BB spindle
2. Remove metal clips from BB cups
3. Press out BB spindle (through either side, but I'll press from non-drive side)
4. Pop out the BB cups using something like headset cup removal tool

Am I in the ballpark??

Thanks,

Martin
mkozaczek is offline   Reply With Quote
Old October 4th, 2011, 4:33 PM   #2
mainlyfats
Senior Member
 
mainlyfats's Avatar
 
Join Date: August 13th, 2004
Location: Winnipeg
Posts: 703
Default

Quote:
Originally Posted by mkozaczek View Post
So, one of my Yos has a completely dead factory BB.

My idea of how to remove the BB is as follows

1. Remove collars from BB spindle
2. Remove metal clips from BB cups
3. Press out BB spindle (through either side, but I'll press from non-drive side)
4. Pop out the BB cups using something like headset cup removal tool

Am I in the ballpark??

Thanks,

Martin
If it's from the factory, then there are no cups, just bearings. As long as they are really truly dead, just use a drift and a hammer and bash them out from the backside.
mainlyfats is offline   Reply With Quote
Old October 6th, 2011, 7:35 AM   #3
rody
Senior Member
 
rody's Avatar
 
Join Date: October 19th, 2005
Location: Wooster, Ohio
Posts: 287
Default

As posted previously on the board (search function is nifty)...

The press in bottom bracket used in the early Fats is not difficult to work with, but takes some understanding.

The bb shell has two internally bored reliefs for the bearings to press into with approximately .004" interference fit. Snap rings on the external diameter of the bearing assure proper insertion depth, as they will sit tightly against the face of the bb shell. The bb spindle is smooth with no shoulders to locate the centerline, instead relying on locking collars that slide over the spindle and pinch to maintain your chosen chainline.

To remove an old set of bearings in the home mechanic setting with minimal tools, you will need a few blocks of wood with padding, a punch with a square head, and a hammer. Remove the spindle locking collars and slide the spindle out of the bb, it may take a gentle tap with a soft head or rubber hammer. Carefully support the frame on it's side on the ground with the blocks of wood and padding supporting the frame tubing. With the spindle out, insert the punch through the top bb bearing and place the head against the inside of the opposite bearing on the outer edge. Gently tap the punch, moving around the bearing in opposite areas to push the bearing out. Consider the bearing like a clock face, working at 9, then 3, then 12, then 6 etc.. Don't get discouraged if the bearing does not move quickly, small even taps and a little patience are your friend to prevent damage.

Once the bearing is out, flip the frame and remove the other bearing in a similar manner.

To install a new bearing, clean the frame's bb area well, gently sand the inside of the bb to remove any rust deposits, then lightly coat the inside of the shell with a thin layer of waterproof grease (like Phil green grease). To install the bearing, work one side at a time to prevent "cocking" of the bearing in the shell.

Gently place a bearing in position with the frame's bb located in a vice between two pieces of straight wood. Rotate the jaws closed until they just contact the bearing and the opposite bb shell face, insure the bearing is straight and true to the shell. Then advance the pressure to insert the bearing to the proper depth. Repeat on the opposite side.

The spindle should be cleaned and lightly greased, then inserted back into the bearings. Slide the collars into place and leave loose. Install your cranks. Once your cranks are installed, adjust the centerline of the chain and then lock down the collars. You should be all set.
__________________
check it out... www.groovycycleworks.com and www.groovycycleworks.blogspot.com !
rody is offline   Reply With Quote
Old October 6th, 2011, 5:35 PM   #4
mkozaczek
Senior Member
 
Join Date: August 11th, 2011
Location: Los Angeles, CA
Posts: 121
Default

Thank you Rody. You should post this on your website for posterity.

An order for some bearings will be coming your way, as well as another set of decals.

Also, I got that Grove Frame on eBay. It's with my other one at Bill's right now =)
mkozaczek is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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

Forum Jump


All times are GMT -5. The time now is 4:59 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.