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Shimano UN55 Square Taper English Threaded Bottom Bracket

Shimano UN55 Square Taper English Threaded Bottom Bracket
Square Taper
Please select options
This item is not permitted to be shipped, however it can be purchased online and picked up. All Special Order bikes/parts/accessories/clothing ordered are final sales, no returns or refunds. ATTENTION Please note all online orders made Friday evening through close on Sunday will not be available until Monday. An email will be sent when the order is ready for pick up.


Shimano's BB-UN55 Square Spindle Bottom Brackets are the unofficial standard for English-threaded cartridge bottom brackets. Quality, value, and durability come together to keep you cranking for many, many miles.

- Fits JIS Square-Taper Cranksets
- Hollow spindle
- Crankarm fixing bolts not included

Part Numbers

Option UPC MPN Store SKU
107mm / English / Square Taper / 68mm 689228778801 EBBUN55B07
107mm / English / Square Taper / 73mm 689228778726 EBBUN55C07
107mm / Italian / Square Taper / 70mm 689228778788 EBBUN55I07
110mm / English / Square Taper / 73mm 689228778825 EBBUN55C10
110mm / Italian / Square Taper / 70mm 689228778771 EBBUN55I10
118mm / English / Square Taper / 73mm 689228778733 EBBUN55C18 CAR78934483K
113mm / Italian / Square Taper / 70mm 689228778856 EBBUN55I13
115mm / Italian / Square Taper / 70mm 689228778818 EBBUN55I15
118mm / Italian / Square Taper / 70mm 689228778849 EBBUN55I18
122.5mm / Italian / Square Taper / 70mm 689228778832 EBBUN55I22