gitaneusa.com :: View topic - Bottom Bracket

vanhelmont

You surely don't want it always coming loose. Inconvenient, troublesome, and surely not good for the parts. I took apart my first bottom bracket when I was about 12, and my uncle gave me a British 3 speed. I got a book from the library. Now all you gotta do is look up the late Sheldon Brown's website.
http://sheldonbrown.com/tooltips/bbcups.html

or here:
http://bicycletutor.com/bottom-bracket/

My method:

1. Take off the lock ring
I don't have a special tool for lock rings. They exist, maybe I should get one, but I either use pump pliers, trying to protect the ring from marring somehow (this marring would only be cosmetic), or lately I have been using a piece of hard wood, placing it against one of the notches in the lock ring and tapping it with a hammer.

2. Take out the adjustable cup
This needs a special tool, a pin spanner. I've had mine for years, I don't know how common they are these days.
http://sheldonbrown.com/harris/tools/bottombracket.html

3. Collect the balls and spindle
Loose balls have a way of escaping. The balls are readily available, and standard for all ball bearing bottom brackets I know of, 1/4 inch.

4. Remove the fixed cup
Usually (for cleaning) you don't do this. You can just clean and grease it in place.

To remove it, I've been using a 12" crescent wrench. My 10" wrench won't open wide enough. Next time I think I'll try the idea Chas wrote above about a bolt to hold the wrench on. A bench vise may be even better.

Sheldon Brown shows a way to use a big bolt to take it out.

Then you can clean it and properly loctite it, clean and grease the bearings, cups, and spindle, and you should be good to go for a year or so.

Dave

verktyg

Nat,

Good pictures, shows the fixed cup coming loose.

The real solution is to take the BB apart to clean and inspect the cups and internal threads.

The problem that you might run into is pulling the crank arms off.

Stronglight cranks have non standard 23.35mm x 1mm extraction threads and use a special puller (more recent Stronglight cranks use standard 22mm x 1mm threads)..

The standard crank arm threads for Campy and most other makes except TA is 22mm x 1mm.

TA cranks have 23mm x 1mm threads. A TA puller will fit loosely in Stronglight cranks but may strip out the threads when you try to remove the crank arms. This would make future removal very difficult.

One question is how did the last person to work on the BB get the crank arms off?

Finding a shop that has the correct puller for Stronglight cranks may be a problem. The pullers show up on eBay but sell for up to $50.

Once you have the the crank arm removal problem solved. You can proceed on to the BB.

Your Stronglight fixed cup is 8 sided rather than 6 or 2 sided.

There are some special tools for removing or installing fixed cups. A good bike shop should have one of these fixed cup tools.

http://tinyurl.com/ah6y6s

Here's an inexpensive solution for keeping an adjustable wrench or Channellock pliers from slipping off of the fixed cup while loosening or tightening it.

Get a 1/2", 5/8" or 3/4" by about 4" long, several nuts to fit the bolt plus several 1 1/2" to 2" diameter flat washers.

Remove the adjustable cup and axle then partially reinstall the cup. Put a washer behind the bolt head and put it through the hole in the fixed cup. Put on the other flat washer and nut on the adjustable cup side.

Place the wrench or pliers over the flats on the fixed cup and snug up the nut on the bolt finger tight. This will help keep the tool on the fixed cup flats.

Blue Loctite on clean fixed cup threads should keep the cup from coming loose again.

Think about this, your bike is 35+ plus years old and for the most part irreplaceable - they don't make these anymore. Use caution when commending your treasure to the hands of another. Make sure that they know what what they are doing, that they are not a "Hammer Mechanic" and that they have the correct tools to do the job.

Chas.

natprice

Thanks for all the help! I don't really have much in the way of tools here with me at college and without the bike to get around I guess I will just order what I need online.

Sounds like what I am going to need is:
1. socket wrench
2. stronglight crank puller
3. C spanner or "spanner wrench" or according to Dave a block of wood and a hammer
4. pin spanner
5. box wrench
6. 5/8 or 9/16" X 1.5" long bolt, nut, flat washer, and 4 lockwashers to make a diy fixed cup remover
7. acetone to remove locktite

Anything else? I guess I will have to start looking on eBay for the stronglight crank puller...

dan lenik

Hi, I figured I better chime in and share this.
I have a Hosteler and YES my left side cup worked loose. There is no shame in using locktight (working perfectly now), but I came across a bit of genius from an ebayer in the UK (charlie the bike monger). It's a YST sealed bottom bracket made for frames that have stripped threads. It looks like a normal square taper bottom bracket with shimano cups. It drops through the drive side (right) and the left cup screws to the bottom bracket instead of the frame making frame threads unnecessary! Of course you wouldn't do this for a restoration,but for a bike you are going to ride it is a perfect upgrade without altering your frame. Good luck with your project! Sincerely, Dan

verktyg

natprice

Thanks for all the help and advice! I ordered the crank puller on ebay and ordered the pin spanner and bottom bracket wrench from Park as suggested by verktyg.

When I pulled the cranks off it took a considerable amount of force. The crank puller came with a 4.5" long, 1/4" diameter, solid aluminum shaft to use in the socket as a lever. I had to hook a large crescent wrench on the end of it and bent the shaft that came with the tool slightly removing the cranks. I am not sure why it took so much force.

I used the bottom bracket wrench to remove the lock ring from the adjustable cup and then just used a wrench to remove the adjustable cup. I didn't need a pin spanner and I don't even see any notches where I would use one.

The fixed cup was loose enough to be turned by hand and I just used a pair of pliers to remove it.

I am planning on cleaning everything and then using blue Loctite on the fixed cup. What is the best way to tighten the fixed cup? What grease should I use when I reassemble everything?

natprice

Here are some photos of the bottom bracket.

http://picasaweb.google.com/NatBPrice/BottomBracket?feat=directlink

The markings on the axle are Stronlight and what appears to be 118. The adjustable cup doesn't appear to require a pin spanner. Is this part of the original bottom bracket or are the axle and cup mismatched?

verktyg

natprice

I am not sure why it keeps coming loose since it seems the only unscrewing force is the friction in the ball bearings. I cleaned all the grease out with mineral spirits so hopefully the Loctite will hold this time.

What grease should I use when I reassemble it?

How exactly does the trick with using the bolt and washers to hold the wrench on the fixed cup work?

Is there a procedure for tightening the cups so that the bearings are properly adjusted?

Any tips for how to Loctite the fixed cup?