JonathanG

I am hoping that someone can give me some advice, or warn me off from doing something extremely stupid. I have been trying to remove a factory-installed square taper cartridge bottom bracket in a bike. I'm doing this because I converting the bike to a fixed gear and want to change the chain line. The bb was in really tight and I couldn't get it to move.

After reading everything I could in the forums I tried a 25" breaker bar with a 1/2" driver along with a bottom bracket to that would fit the driver. I was able to get the drive side out and remove the cartridge with the spindle (the brand appears to be "First") but the non-drive side wouldn't budge. So, after again consulting the forums I tried using Liquid Wrench, heating the bottom bracket and then applying the breaker bar and the bottom bracket tool with all my strength and weight, and given that I'm not exactly in racing form that's quite a bit. Still, the non-drive side wouldn't move.

I'm thinking of taking a hack saw to it but am concerned about damaging the threading. Another thing I was thinking of is just leaving the non drive side in there in place of the non-drive side retainer of the replacement bb, but I'm not sure if this would work for different length and different brand (Shimano UN 52) of bb.

Any advice or warnings would be appreciated.

Thanks,

Jonathan

Raiyn

Steel or Aluminum frame?

JonathanG

Aluminum.

Raiyn

I knew it.
Pour Ammonia down the seat tube. It will break the Aluminum oxide bond between the Aluminum frame and the steel BB. Liquid Wrench isn't worth a damn against Aluminum Oxide

JonathanG

Thanks, I'm willing to try anything.
Should I reinstall the cartridge and drive-side retainer to hold the ammonia in, or should I just slosh the ammonia onto the area around the non-drive side retainer? Any advice on how much or how long I should leave it on?
Again, thanks! I really appreciate the advice.
Jonathan

Raiyn

Put the cartridge and drive side back in (grease them first) to contain the liquid. Try it at five minutes if it doesn't work wait longer. Also do this in a well vented area.

MudPie

Just want to verify: For non-drive side, remove by turning counter-clockwise. For drive side, turn clockwise to remove.

JonathanG

Thanks. I'm aware of that, but it's obviously important to get it right, and I do appreciate all advice and comments.

I'll be trying the ammonia down the seat tube tomorrow.

Jonathan

tellyho

Also, hitting the breaker bar sharply will sometimes get things done where a consistent force won't. You could also put the BB tool in a bench vice and use the bike frame as your lever.

The cup that's in there might work with a new cartridge. You might as well try that, too. Good luck.

acroy

I had a STUCK bb in my first mtb bike (steel), it took a 6-foot breaker bar to get it out. My (overweight) sister had to stand on the handlebars as I tugged on the breaker bar.
Best o luck.

phoebeisis

Hmmmm, don't some-french-BB unscrew the "normal" way-both cups counterclockwise?
Every 10 years I manage to forget the oddball left side unscrewing?
A very sharp blow with a 2-4 lb hammer or a decently long 2x4 is the way to go.tELLYHO is dead right-you have to put the breaker bar on-tension it so your"wrench" is in full contact with the cup, and give the breaker bar several hard raps.One other trick is to give it a much softer rap in the wrong direction just before giving it the hard raps in the right direction.
Hard jolts are much, much more effective than steady force at breaking something lose.Steady force,slowly increased can round the part off , but the hard rap will break it loose.
This is a two man job-one holds the breaker bar in place and tensions it, the other hits it-careful of that frame-if the hammer slips....
It can be done with one man, but two is much, much easier.
Luck,
Charlie
PS-The hard raps are why impact wrenches of all kinds(manual-pneumatic-electric) work so well.

MB4

Hey Jonathan, let us know how the ammonia works out. I have an aluminum frame with a stuck bb too. The bb creaks when I pedal hard, and its driving me nuts. I can't remove the bb to find the creak.

JonathanG

First, I'd like to thank all the people who have made suggestions. I wish people where I work were as helpful as the people here!

Here's the situation so far. I tried soaking with ammonia for 10 min, 1 hour, and then overnight. The ammonia definitely dissolved a lot of aluminum oxide -- the interior of the bottom bracket shell and the seat tube are really shiny now, and if were only a matter of aluminum oxide I'm sure the ammonia would have worked -- but the non-drive-side retainer is still stuck. The real problem is that the mfgr put in the bb so %&#@ing tight! Why? I'm worried that I've started to strip the indentations on the stuck retainer, because I haven't been able to hold the bb tool in, hold the frame down, and torque the breaker bar all at the same time. I guess another problem might be that I've been doing this by myself without help. Next weekend I'll get a friend to help. I suppose I could use my somewhat overweight brother but he lives in a different city!

For now I've just installed the new cartridge with the old, stuck, non-drive side retainer, and it seems to fit. Should I be worried? I'm really annoyed at the old cup, which looks really bad now and will be a constant reminder of my failure.

Hitting the breaker bar sharply sounds like a good idea, but it seems hard with the swivel type of breaker bar I have, but I may not be thinking about, or doing it, correctly. Another thing to try will putting a bb tool in a bench vise and using the frame as the leaver, but I don't have ready access to a bench vise. Does anyone have any opinion on trying to hack saw the stuck cup out?

Again, thanks again for all your help and interest!

Jonathan