This item for sale is a new Shimano cartridge (sealed) bottom bracket...model BB-UN54. Some of it's specifications include the following:
Cup type/size: English threaded...1.37" cups x 24 threads per inch (tpi)
Shell width: 68 mm
Spindle/axle type: JIS square-tapered
Spindle/axle length: 113 mm
Production locale: Made in Singapore...please note Shimano authorized the additional production of this particular square-tapered (50-series) bottom bracket after the intended crankset matches were out of current production. This decision was made, because of the demand for this model/size bottom bracket from those that still had serviceable cranksets requiring these bottom bracket specs. It's a newer offering produced outside of Japan, but we still refer to the unit as a new-old-stock bottom bracket. This is the case, because we do not want to mislead someone into thinking it is compatible with Shimano's current production cranksets.
Please note the spindle/axle length is fairly important, because Shimano made this model bottom bracket in several spindle lengths to accomodate a handful of different cranksets.
Our research further indicates the early 90's Deore LX triple crankset (Models FC-M560) is a good example of a mountain bike crankset match for this bottom bracket. This model crankset was spec'd with two different spindle lengths...with the 113 mm length considered ideal when a 47.5 mm chain line was desired (measured from the center of the seat tube to the middle chainring on a triple crankset). We believe this chain line was usually desired when the front derailleur was mounted on a standard sized seat tube.
Additionally, the mid and late 90's Deore LX triple cranksets (Models FC-M563 and FC-570) and all mid to late 90's STX-RC triple cranksets represent other good examples of mountain bike crankset matches for this bottom bracket. We even noted slightly newer Deore model triple cranksets from the early part of this decade (Models FC-M480 and FC-M510...the latter before it converted to Octalink technology) are also good examples of mountain bike crankset matches for this bottom bracket. All of these model cranksets were spec'd with at least two different spindle lengths...with the 113 mm length generally considered ideal when a 50 mm chain line was desired. We believe this chain line was usually desired when the front derailleur was mounted on an oversized seat tube...pushing the front derailleur further to the right.
As for applicable road crankset offerings, the Shimano Sora and Tiagra triple cranksets (Models FC-3303 and 4403, respectively) are also considered a good match for this bottom bracket.
The square-tapered spindle ends are compatible with other vintage 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.
One other note...the left-side adjustable cup is made from a resin/plastic, which is common for Shimano 50-series and below cartridge bottom brackets. We prefer the aluminum alloy adjustable cups found on Shimano's higher-end cartridge bottom brackets, so we wanted to be clear this offering is of inferior quality in this one regard.
As for condition, these units are new and in their original retail box.
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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.