Bottom Braket Lockring/Cup
#1
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From: western Nevada
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Bottom Braket Lockring/Cup
Hi,
I'm having difficulty removing the left side cup and lockring on my mid 80's stumpjumper. It won't move when I wrench it. I used penetrating oil, but it is stuck. What should I do to get it to loosen up and remove it?
Jeff
I'm having difficulty removing the left side cup and lockring on my mid 80's stumpjumper. It won't move when I wrench it. I used penetrating oil, but it is stuck. What should I do to get it to loosen up and remove it?
Jeff
#2
Old fart



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From: Appleton WI
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What have you tried at this point? You should use a hooked spanner to remove the lockring, like the upper tool in this picture:

Once the lockring is off, you can use a pin spanner to remove the cup:

Bike shops often have more effective (and expensive) tools they can bring to bear if you can't do the job with the tools you have at home.

Once the lockring is off, you can use a pin spanner to remove the cup:

Bike shops often have more effective (and expensive) tools they can bring to bear if you can't do the job with the tools you have at home.
#3
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Single hook is most often insufficient, i.e. sufficient for destroying the lockring but insufficient for moving it. Few grab points are preferred. Otherwise, to remove the cup, you need secure the BB tool with a bolt+washer screwed into the axle of BB, to keep the tool in place.
#4
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From: New Rochelle, NY
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
Sometimes it takes more than gentle force to pop off an old lockring. This is the tool of choice used by old timers who do lots of these. If you don't want to buy or borrow one, consider letting the LBS do this job, or simply set an old dull chisel into one of the notches and giving it a sharp hammer blow. Don't tap it, that just drives the chisel in, give it a meaningful shot which should sent it spinning off.
Once the lock ring is off you can try the cup, but if it's rusted in there's a good chance that it'll shear the pins off a two pin tool. There were 6-pin tools back in the day for stubborn cups, but i don't know if they can be had today. If 2-pins isn't enough, and you have a small home shop, you can make a 6-pin tool yourself from scrap metal, or resort to desperate measures. Try driving the cup out with a chisel or punch set into a hole, or try grabbing the cup with a big pair of Channellocks, or try clamping the cup in a vise and turning the frame.
If it's really seized, you might try getting the right side off first (Don't forget that many are left hand threaded) then using a fine thread 9/16" bole and nut to work the left off.
Once the lock ring is off you can try the cup, but if it's rusted in there's a good chance that it'll shear the pins off a two pin tool. There were 6-pin tools back in the day for stubborn cups, but i don't know if they can be had today. If 2-pins isn't enough, and you have a small home shop, you can make a 6-pin tool yourself from scrap metal, or resort to desperate measures. Try driving the cup out with a chisel or punch set into a hole, or try grabbing the cup with a big pair of Channellocks, or try clamping the cup in a vise and turning the frame.
If it's really seized, you might try getting the right side off first (Don't forget that many are left hand threaded) then using a fine thread 9/16" bole and nut to work the left off.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#6
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From: western Nevada
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Ok, thanks for the great advice. I actually ordered the park tools necessary for the job.
Now the stupid question, which way do I turn it off? Right or left?
Jeff
Now the stupid question, which way do I turn it off? Right or left?
Jeff
#7
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From: New Rochelle, NY
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
To clarify, It's a RH thread so you turn it counter-clockwise to loosen.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#8
Old fart



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From: Appleton WI
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