This item for sale is a new-old-stock (nos) Shimano 105 "cup-n-cone" bottom bracket...model BB-1050. Some of it's specifications include the following:
Cup type/size: Italian threaded...36 mm cups x 24 threads per inch (tpi)
Shell width: 70 mm
Spindle/axle type: JIS square-tapered with 5H markings
Spindle/axle length: 115 mm
Special note: The spindle/axle has symmetrical measurements, as both the right and left side spindle ends (including the width of the cone) measure 31 mm and the center section measures 53 mm.
Please note the spindle/axle length is fairly important, because Shimano cranksets (and other brands) generally have different profiles. This is key, because it's the combination of the bottom bracket spindle length and the right-side crank arm profile that will have the greatest impact on chainline. There is not as much information on these older style cup-n-cone bottom brackets, but we believe Shimano's chainline recommendations (for their cup-n-cone bottom brackets) should be consistent with their newer cartridge bottom bracket offerings. Assuming this fact, a chainline of 43.5 mm (measured from the center of the seat tube to the midpoint between the two chainrings on a double crankset) or a chainline of 45.0 mm (measured from the center of the seat tube to the middle chainring on a triple crankset) is considered optimal for a road bike. Alternatively, a chainline of 47.5 mm (measured from the center of the seat tube to the middle chainring on a triple crankset) is considered optimal for a mountain bike. The only other consideration here is that Shimano also specifies that a 50.0 mm chainline may be preferred for a mountain bike when the front derailleur is mounted on an oversized seat tube...pushing the front derailleur further to the right.
Given these parameters, there are probably a number of cranksets that may be compatible with this bottom bracket...although our research indicates that Shimano's 105 crankset from the late 80's (double chainring model FC-1050) is compatible and the intended match for this bottom bracket. As a result, this offering is a decent quality bottom bracket from this period. It's not high-end Ultegra or Dura-Ace quality, but it still seems to be a serviceable bottom bracket unit at a much lower cost.
Please also note that while this Shimano 105 bottom bracket is less expensive than the early 90's successor model we also have available, there were some sealing design features included with the early 90's model that are not present here...which may help account for the price difference. More specifically, this offering does not include the rubber-like ring inserts that line the inside of each cup to prevent dirt and other elements from entering through the spindle/axle opening. Additionally, this retail boxed offering does not include the flexible plastic sleeve that presses against the inside of each cup to form another seal to keep dirt and other elments from getting to the bearings or races from other openings in the frame (i.e., seat tube opening for the saddle, etc).
Also (and as noted above), the square-tapered spindle ends are compatible with other Shimano cranksets, but please check your crankset's spindle/axle length requirements before attempting to use this offering with another Shimano crankset...and we can try to help in this regard should you have questions). We empasize this last point, because chainline has a direct impact on shifting performance, so even though selected Shimano crank arms may have the same square-tapered interface, if their spindle/axle length requirements are different from this offering, then there is a strong possibility that shifting performance will suffer...so please pay particular attention to spindle lengths when it comes to purchasing any bottom bracket.
As for condition, these units are new and in their original retail box...so very nice cosmetic condition.
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Note to international customers regarding shipping...
We apologize to those that feel some of our international shipping charges are too high. We only charge actual shipping rates, but once an order exceeds a certain amount, we hesitate to use the least expensive US Postal Services First Class International service. We feel this way, because this service is not trackable or insurable...so more risk of loss. We prefer the US Postal Services Priority Mail International service for more expensive orders, because this service is trackable at USPS.com and insurable...so less risk of loss. Unfortunately, this service is more expensive, especially for smaller/lighter packages, relative to the First Class International service. We are sorry about these higher shipping costs, but hopefully our notes help to explain why this is the case.
Note to international customers regarding customs...
We also apologize to those that feel their country import taxes, duties and brokerage fees are excessive. As a small US business, we are required by customs' laws to declare each order as a retail sale. Additionally, the declared order value must be equal to total store purchases and/or winning auction bids (less any shipping costs, as these are not considered in the declared value). As a result, each customer will be responsible for paying his/her own country taxes, duties and brokerage fees, which will be collected upon delivery. Again, we apologize for these additional costs, but we cannot afford the penalties and fines that come with breaking customs' laws...so we have to strictly abide by them.