Bottom Bracket Cup Stripped

I'm just going to fill up some space on the post before some people who actually know what they're talking about come in. But would it be possible to just drill out the cup at the expense of the BB shell threads and install a threadless BB... 😕

i want to avoid that option if possible, but i have read about that possibility.

Can you drill small holes into the face of the cup?
If you can, then drill small (1.5mm diameter) holes at least 10mm deep into the face of the cup (see black lines in attached image). Punch 20 mm steel pins of 1.5mm diameter into holes.

Then:
a] Drill matching 1.6mm diameter holes in center of 30cm long, 5mm thick x 20mm wide steel bar, place steel bar over pins and use as a lever to unscrew the cup.

or

b] Just use the long steel bar between the pins to unscrew the cup

I would go for option [a] first, since this will give a more positive engagement of the pins with less chance of just bending them without actually unscrewing the cup.

Good luck

hi,
suggestion 1.
using a flat piece of hard wood trimmed just over the bb shell aperture width.
drive it into the bb shell so it sticks out like a long spindle.
try and turn the wood with a large adjustable shifter or even attached another piece of wood as a handle so it forms a large "t".
suggestion 2
may also be able to drive into the aperture a piece of flat steel plate [may have to taper it slightly]and try and turn that.
suggestion 3
use length of broom stick or similar just over aperture dia and drive etc
attach handle or lock jaw pliers or stiltsons

sjsielen said:

As you can see in the attached photos, the aluminum cup from a Race Face ISIS SRX bottom bracket has been totally stripped and warped. This is in a Cannondale 98 aluminum caad2 frame. This is a project my brother is working on, with much frustration, and I just thought I could ask all of you out there for any opinions. I did read these posts/sites:
cyclingforums.comt39555.htmlOpen ↗
cyclingforums.comshowthread.phpOpen ↗
parktool.comhowfix bbtap.shtmlOpen ↗
parktool.comFAQcartdg.shtmlOpen ↗
but we are still unsure of what to do do remove this warped bb cup. As you can maybe tell, my brother used a dremel to remove parts of the cup hoping to use it for leverage, but it still will not budge.

Use a hacksaw blade and make about 6 cuts through each cup being careful not to get into BB threads. Work with screwdriver or other tool to pry out pieces. The threads may need to be chased to clean hem up.If threads are badly buggered the shell can be rethreaded to Italian.

Julian Radowsky said:

Can you drill small holes into the face of the cup?
If you can, then drill small (1.5mm diameter) holes at least 10mm deep into the face of the cup (see black lines in attached image). Punch 20 mm steel pins of 1.5mm diameter into holes.

Then:
a] Drill matching 1.6mm diameter holes in center of 30cm long, 5mm thick x 20mm wide steel bar, place steel bar over pins and use as a lever to unscrew the cup.

or

b] Just use the long steel bar between the pins to unscrew the cup

I would go for option [a] first, since this will give a more positive engagement of the pins with less chance of just bending them without actually unscrewing the cup.

Good luck

As if them tiny pins would stand up to any force applied to them.

sjsielen said:

As you can see in the attached photos, the aluminum cup from a Race Face ISIS SRX bottom bracket has been totally stripped and warped. ..., my brother used a dremel to remove parts of the cup hoping to use it for leverage, but it still will not budge.

Go with Boudreaux suggestion, cut through the cup while being careful of the threads and then pry it out. If you make the cuts where you have a bit of flange still protruding you can put a chisel against the remaining flange and hit it inwards with a hammer. If sawing feels scary you can use the Dremel and grind your way through instead.
Small damages to the threads aren't critical for strength, but can make it harder to get the new cut properly aligned when installing.

Boudreaux is right. Those cuts will relieve the tension on the threads and you can peel the pieces out like a banana.

take your time

boudreaux's idea about trying to cut it into pieces and then pry/peel them out is what I thought might work, but was unsure about damaging the threads.

Saw it out with a hack saw. I did this once. I think it only required two cuts.

sjsielen said:

boudreaux's idea about trying to cut it into pieces and then pry/peel them out is what I thought might work, but was unsure about damaging the threads.

you don't have to go as deep as the threads. You just have to loosen the tension on the thread interface and it may spin out easily. If not just peel it out.

hope this makes sense

yeah that makes sense. i am having someone drop off a hack saw tomorrow and i will let you all know how things turn out and maybe take some pictures during the process.

lumpy said:

you don't have to go as deep as the threads. You just have to loosen the tension on the thread interface and it may spin out easily. If not just peel it out.

hope this makes sense

started with the hack saw, but soon after switched to using a file. finally used a chisel to take severed piece out. threads barely touched inside bb shell.

to future people with this problem... use a FILE with patience.

😄