Why doesn't my BB thread all the way in?
06-21-17 | 04:44 PM
#1
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From: Tucson
Bikes: Lemond Zurich, All City Macho King Ace
Why doesn't my BB thread all the way in?
Why doesn't this BB thread all the way in? It says 68mm on the BB itself and the shell is a 68mm (Surly CC). I'm replacing the BB with the exact same model it had before.
Ride like this? Get a spacer? What to do?
Ride like this? Get a spacer? What to do?
06-21-17 | 05:27 PM
#3
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From: St Peters, Missouri
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Do you have a screw securing a bottom bracket cable guide?
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06-21-17 | 05:32 PM
#5
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From: Tucson
Bikes: Lemond Zurich, All City Macho King Ace
No screws in the BB shell. It's a single speed setup so I took the cable guide off. The exposed threads don't really bother me. I was just wondering if I should do something about it or not.
06-21-17 | 05:35 PM
#6
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did you thoroughly clean the frame's threads with a wire brush?
did you apply a bit of grease to the threads before installing the new BB assembly?
if yes to both questions, then you should quit worrying, and go ride the bike.
the inside of that part of the BB assy. is slightly tapered, to allow for proper alignment and a snug fit.
ride it.
did you apply a bit of grease to the threads before installing the new BB assembly?
if yes to both questions, then you should quit worrying, and go ride the bike.
the inside of that part of the BB assy. is slightly tapered, to allow for proper alignment and a snug fit.
ride it.
06-21-17 | 05:42 PM
#7
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From: Tucson
Bikes: Lemond Zurich, All City Macho King Ace
did you thoroughly clean the frame's threads with a wire brush?
did you apply a bit of grease to the threads before installing the new BB assembly?
if yes to both questions, then you should quit worrying, and go ride the bike.
the inside of that part of the BB assy. is slightly tapered, to allow for proper alignment and a snug fit.
ride it.
did you apply a bit of grease to the threads before installing the new BB assembly?
if yes to both questions, then you should quit worrying, and go ride the bike.
the inside of that part of the BB assy. is slightly tapered, to allow for proper alignment and a snug fit.
ride it.
06-21-17 | 09:09 PM
#8
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If not, you're in deep enough and good to go. If you feel some movement, back the thing out and start over.
06-21-17 | 09:11 PM
#9
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Bikes: 1991 Bianchi Eros, 1964 Armstrong, 1988 Diamondback Ascent, 1988 Bianchi Premio, 1987 Bianchi Sport SX, 1980s Raleigh mixte (hers), All-City Space Horse (hers)
Totally normal. Finish assembling bike and ride. 
06-21-17 | 09:13 PM
#10
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From: Tucson
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...the purpose of those installation cups on a sealed unit like yours is to go in far enough that the tapered inner circumference of the cup fixes the casing of the sealed unit firmly in place within the BB shell. When you put the crank arms on, grab them and see if you can feel any movement when you rock them perpendicular to the plane of rotation.
If not, you're in deep enough and good to go. If you feel some movement, back the thing out and start over.
If not, you're in deep enough and good to go. If you feel some movement, back the thing out and start over.
06-21-17 | 10:17 PM
#11
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From: NE Italy
Perhaps, I am being a little anal, but on the bikes I've worked on, the left side of the bike, the cup was screwed on first until flush, then the right side was screwed on. I don't know if this makes a difference.
06-21-17 | 11:14 PM
#12
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