2015 Specialized Venge Expert - OSBB - aluminum "inner shell"?
05-16-15, 06:43 PM
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2015 Specialized Venge Expert - OSBB - aluminum "inner shell"?
A few months ago I purchased a 2015 Specialized Venge Expert Ultegra:
Specialized Bicycle Components
The specs says it has "carbon OSBB" bottom bracket.
Looking at the bottom bracket there is a silver ring around the bottom bracket on both sides. It looks exactly like this picture:
from this document:
https://fairwheelbikes.com/assets/ma...ide_ConvBB.pdf
That document says that the Specialized bikes with that have an "aluminum inner shell" and that those bikes are 68mm across at the bottom bracket. A rough measurement of mine shows it's much closer to the 61.5mm with the carbon inner shell.
So what is with the silver ring? Is it an aluminum inner shell or what?
Reason being is that this bike creaks like a sonofa*****. I'm halfway contemplating putting in a BBInfinite or an Enduro TorqTite. But before doing so I need to have an idea of what is in my bike.
Specialized Bicycle Components
The specs says it has "carbon OSBB" bottom bracket.
Looking at the bottom bracket there is a silver ring around the bottom bracket on both sides. It looks exactly like this picture:
from this document:
https://fairwheelbikes.com/assets/ma...ide_ConvBB.pdf
That document says that the Specialized bikes with that have an "aluminum inner shell" and that those bikes are 68mm across at the bottom bracket. A rough measurement of mine shows it's much closer to the 61.5mm with the carbon inner shell.
So what is with the silver ring? Is it an aluminum inner shell or what?
Reason being is that this bike creaks like a sonofa*****. I'm halfway contemplating putting in a BBInfinite or an Enduro TorqTite. But before doing so I need to have an idea of what is in my bike.
05-16-15, 06:57 PM
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I'm sure the sliver is aluminum. They rarely (if ever) use just carbon resin there because metal is a far better choice down there due to threading on classic BBs, the torque of compression for press-fit BBs, & the lips that hold the cartridge bearings of the press-fit BBs.
As for the creaking, exactly what bottom bracket / crankset are you using? This can be due to many things, but perhaps we can narrow it down with this info.
As for the creaking, exactly what bottom bracket / crankset are you using? This can be due to many things, but perhaps we can narrow it down with this info.
05-16-15, 07:00 PM
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The bike was purchased brand new. The bottom bracket hasn't been changed from what came new in box from the factory. The stock crankset was removed and a Rotor 3D+ Power2Max TypeS was installed. Creak/click started around 500 miles in.
05-16-15, 07:11 PM
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I'd take it for a ride and see if there's a trend in the creaking on arm rotation position or torque. Also, who installed it? Has it been re-installed? (I'm guessing so with the photo).
My first thought was an uneven tension of bolts or needed an adjustment of pressure on bearings. Then upon seeing what crank is being used, is it something to do with the power meter system inside the crank. Not the bottom bracket? I highly doubt it has anything to do with the BB shell you've pictured.
My first thought was an uneven tension of bolts or needed an adjustment of pressure on bearings. Then upon seeing what crank is being used, is it something to do with the power meter system inside the crank. Not the bottom bracket? I highly doubt it has anything to do with the BB shell you've pictured.
05-16-15, 07:13 PM
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I'd take it for a ride and see if there's a trend in the creaking on arm rotation position or torque. Also, who installed it? Has it been re-installed? (I'm guessing so with the photo).
My first thought was an uneven tension of bolts or needed an adjustment of pressure on bearings. Then upon seeing what crank is being used, is it something to do with the power meter system inside the crank. Not the bottom bracket? I highly doubt it has anything to do with the BB shell you've pictured.
My first thought was an uneven tension of bolts or needed an adjustment of pressure on bearings. Then upon seeing what crank is being used, is it something to do with the power meter system inside the crank. Not the bottom bracket? I highly doubt it has anything to do with the BB shell you've pictured.
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atlantic90
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07-23-15 07:19 AM
