After removing the bottom bracket cups on my old Schwinn World bicycle (spindle is 124.5 mm (3S) type) I found the cups look just like the ones labeled BB-651 on the following YST product page. I came by a set of BB-633 cups and bearings on the same YST page.
The BB-633 seems to fit fine, except the fixed cup stands out about 1/16"-1/8" further than the BB-633 type. I did a test fit of the crankset and everything seems to clear so the standout seems ok..
My question is this. Other than the obvious difference in wrench types to remove the fixed cup (I used Sheldon's homemade bolt and nut fixed cup remover for that anyway), and the amount the BB-633 stands out, is there any difference in these cups and bearings? Does anyone know what they mean by the term, "U-type chain case," used to describe the BB-633?
After removing the bottom bracket cups on my old Schwinn World bicycle (spindle is 124.5 mm (3S) type) I found the cups look just like the ones labeled BB-651 on the following YST product page. I came by a set of BB-633 cups and bearings on the same YST page.
The BB-633 seems to fit fine, except the fixed cup stands out about 1/16"-1/8" further than the BB-633 type. I did a test fit of the crankset and everything seems to clear so the standout seems ok..
My question is this. Other than the obvious difference in wrench types to remove the fixed cup (I used Sheldon's homemade bolt and nut fixed cup remover for that anyway), and the amount the BB-633 stands out, is there any difference in these cups and bearings? Does anyone know what they mean by the term, "U-type chain case," used to describe the BB-633?
On Thu, 05 Aug 2004 01:51:47 -0400, smyrna45 <[email hidden]>
Quoted message said:
Does anyone know what they mean by the term, "U-type chain case," used to describe the BB-633?
A chain case is like a chain guard, but encloses the chain completely (top and bottom runs). MODEL SBHCC - 294 (FULL GEAR CASE) is shown at http://www.safaribikes.com/mud.htm
I'm guessing here, but a U-type chain case may have a bracket that installs using part of the fixed cup.
On Thu, 05 Aug 2004 01:51:47 -0400, smyrna45 <[email hidden]>
Quoted message said:
Does anyone know what they mean by the term, "U-type chain case," used to describe the BB-633?
A chain case is like a chain guard, but encloses the chain completely (top and bottom runs). MODEL SBHCC - 294 (FULL GEAR CASE) is shown at http://www.safaribikes.com/mud.htm
I'm guessing here, but a U-type chain case may have a bracket that installs using part of the fixed cup.
Thanks Dianne. I bet you are right about the chain case. The fixed cup on the BB-633 has a extra set of threads beyond its lip, which jut out another 1/8" to 3/16" or so. This would be a perfect place to attach that enclosed chain guard with a hole big enough to slip over it. Probably why they provided another lockring too for the fixed cup side.
