Listing Update...This offering is for a legitimate new-old-stock Shimano cartridge bottom bracket that was made in Japan. We also want to emphasize this offering includes the aluminum alloy adjustable cup and not the less expensive resin/plastic cup found on many of Shimano's newer model bottom brackets.
This offering for sale is a new-old-stock Shimano cartridge (sealed) bottom bracket...model BB-UN72. Some of it's specifications include the following:
Cup type/size: English threaded...1.37" cups x 24 threads per inch (tpi)
Shell width: 73 mm
Spindle/axle type: JIS square-tapered
Spindle/axle length: 122.5 mm
Production locale: Made in Japan
Please note the spindle/axle length is fairly important, because Shimano made this model bottom bracket in several spindle lengths to accommodate a handful of different cranksets.
Our research further indicates the late 80's to early 90's Deore XT triple crankset (Models FC-M730) is the factory match for this bottom bracket (so this a high-end bottom bracket unit for it's era). Some other information on the crankset/bottom bracket is to note the Deore XT groupset was top-end among Shimano mtb offerings until 1992 (when Shimano introduced the XTR mtb groupset).
The Deore XT crankset from this era was spec'd with two different spindle lengths...with the 122.5 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.
Date coding on this particular bottom bracket indicates a '99 production date, so after the production window for the Deore XT crankset factory match. Although, this is not all that uncommon, as we've noted other instances where Shimano will authorize bottom bracket production runs at later dates to accommodate the needs of older model cranksets still in circulation.
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 emphasize 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 out of an aluminum alloy, which is a little heavier than the resin/plastic adjustable cups we usually note on 50-series bottom brackets. Having said this, we prefer the aluminum alloy adjustable cups, because they are stronger (and this is an area...the bottom bracket shell area...where we believe the added strength is more beneficial relative to the slightly heavier weight).
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.