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Shimano Bottom Bracket Bb-un300 Square Spindle 68 X 123mm

4.254 product ratings

Gap30 Cycles (70634)

99.4% positive Feedback

Price:

US $20.34

Approximately£15.04

+ $16.84 postage

Estimated delivery Thu, 9 Oct - Fri, 17 Oct

Returns:

30 days return. Buyer pays for return postage. If you use an eBay delivery label, it will be deducted from your refund amount.

Condition:

New

Shimano BB-UN300 Bottom Bracket - English, 68 x 122.5mm Spindle, Square Taper JIS, 50mm Chainline. Shimano BB-UN300 Square Spindle Bottom Brackets. Spindle Interface Type: Square Taper JIS. Hollow spindle.

About this product

Product Identifiers

BrandShimano

GTIN0192790619255

UPC0192790619255

eBay Product ID (ePID)10039851812

Product Key Features

Spindle TypeSquare Taper - JIS

ColorBlack

Shell Width68 mm

Bottom Bracket Shell TypeBSA (English)

Compatible Bike TypeHybrid Bike, Cruiser, Mountain Bike, Road Bike, Touring Bike

Part TypeBottom Bracket

MaterialAluminum, Steel

ModelBB-UN300 Bottom Bracket

Dimensions

Item HeightBSA

Length5.39

Item Weight1.0000

All listings for this product

item 1 Shimano BB-UN300 Bottom Bracket - English, 68 x 122.5mm Spindle, Square Taper JI

£15.04

+ £12.24 postage

item 2 SHIMANO Bottom Bracket BB-UN300 Square Spindle 68 x 122.5mm

£17.74

+ £12.32 postage

item 3 Shimano BB-UN300 JIS Square Taper Bottom Bracket 68x122.5mm with Hollow Spindle

£18.13

+ £12.33 postage

item 4 Shimano BB-UN300 Bottom Bracket Eng 68x122.5mm (123mm), Square Taper JIS 50mm

£18.56

+ £12.34 postage

item 5 Shimano BB-UN300 Bottom Bracket - English, 68 x 122.5mm Spindle, Square Taper JI

£20.77

+ £12.41 postage

item 6 Shimano BB-UN300 Standard Structure Bottom Bracket Square Type

£28.48

+ £12.63 postage

listings for this product

Ratings and reviews

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4.3

4 product ratings

3 users rated this 5 out of 5 stars
0 users rated this 4 out of 5 stars
0 users rated this 3 out of 5 stars
1 users rated this 2 out of 5 stars
0 users rated this 1 out of 5 stars

Would recommend

Good value

Good quality

Most relevant reviews

by pseudocoo
16 Sep, 2022
OK on a budget, but higher quality BB's are available. "You get what you pay for"!
Pros - Priced right. Turns smoothly. Cons - Bearings are smaller than other BB's. Aluminum caps are soft and easily dinged. Chinese knock-off tool does not fully engage the 20 notches in the caps - Park tool works OK. The "K" version comes with a spacer on the drive side that needs to be removed for normal use. Shell cavity must be free of any protrusions such as screw tips from cable guides, or tube ends that protrude into the shell cavity. Axle is solid (heavy). This is not typical of Shimano quality! If you are replacing a sealed bearing BB, installation should be straight forward. Recommend a higher quality unit unless there are budget constraints.
Verified purchase: YesCondition: New
by apostle707
25 Jun, 2025
Good bottom bracket at a good price !
Great quality bearings and overall light weight product used but like new
Verified purchase: YesCondition: Pre-owned
by bren_2907
16 Feb, 2021
Shimano BB
Upgraded my 1991 Trek 720. BB is exact fit. Good product.
Verified purchase: YesCondition: New