Sealed bb on loose bb cups
#1
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From: South Italy
Bikes: BMC SLR01; Cannondale Trail; Custom steel gravel.... plus 5 vintage
#2
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From: Mission Viejo
Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970
I'm guessing you are using the sealed bearing spindle with the cartridge bearings against the spindle shoulder. The chamfered edge of the outer cartridge bearing race is all that is making contact with the race in the cup.
I think it would work for a very short term, until the lack of radial and lateral support on the outer race causes it to fail.
Individual cartridge bearing bottom brackets that I have used have a cups that support the outer race of the bearings on the flat surface, not just at a edge single point. There is also a separate pre-load against the outer race to keep it snug without stressing it. What you are doing is trying to juggle both against a corner edge.
John
I think it would work for a very short term, until the lack of radial and lateral support on the outer race causes it to fail.
Individual cartridge bearing bottom brackets that I have used have a cups that support the outer race of the bearings on the flat surface, not just at a edge single point. There is also a separate pre-load against the outer race to keep it snug without stressing it. What you are doing is trying to juggle both against a corner edge.
John
#3
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From: San Jose (Willow Glen) Ca
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best guess is not for very long
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#4
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From: Kingwood, TX
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Short Answer: Yes, it is a bad idea.
Follow your gut instinct.
Follow your gut instinct.
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1984 Cannondale ST
1985 Cannondale SR300
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1981 Trek 710
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#8
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From: Mich
Bikes: RSO E-tire dropper fixie brifter
That is a realllll temp setup that even I wouldn't expect it to make it worth my time to experiment with lol.
I've often wondered why hasn't a "conversion" been produced to a sealed bearing in a part once the races are pressed out. A thicker outer sealed bearing surface seems doable. Definitely would not be a common item, but it shouldn't be that horrible for the tooling to be created in order to make such oddity exist.
I've often wondered why hasn't a "conversion" been produced to a sealed bearing in a part once the races are pressed out. A thicker outer sealed bearing surface seems doable. Definitely would not be a common item, but it shouldn't be that horrible for the tooling to be created in order to make such oddity exist.
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#9
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From: Mission Viejo
Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970
The industry already came up with a conversion when sealed bearing bottom brackets became available. I would guess a very high percentage of square taper cranks are mated to one of these.
The market for a drop-in sealed cartridge bearing replacement for caged/loose ball bearings has to be minuscule.
John
The market for a drop-in sealed cartridge bearing replacement for caged/loose ball bearings has to be minuscule.
John





