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DanmarkShimano BB-UN300 Square Taper BSA Bottom Bracket
Shimano BB-UN300 Square Taper BSA Bottom Bracket
33 reviews
RRP 97,80
76,30
- Delivery in 3 working days
- Free tracked shipping over 400,00 zł
- Trustpilot rating 4.6/5
Pros & Cons
Pros & Cons
- This bottom bracket is easy to install yourself.
- The bearings rotate smoothly and have a good durability.
- This bottom bracket is on the heavy side.
Specifications
Specifications
| Brand | Shimano | |
| Types Screw Thread | BSA | |
| Suitable for | Race / MTB | |
| Crankset axle fit | Square Taper | |
| Bottom bracket diameter | 33.6-33.9 mm |
This Shimano BB-UN300 bottom bracket is a solid and smooth-running square taper bottom bracket. You can easily mount the matching crank on it and it has a good durability.
High quality and performance
This Shimano BB-UN300 square axle bottom bracket in the Alivio range has a very strong and durable design, allowing you to transfer power to your wheels with as little resistance as possible. The axle is made of steel and the bearings are well sealed. This makes this bottom bracket durable and low-maintenance!
High quality and performance
This Shimano BB-UN300 square axle bottom bracket in the Alivio range has a very strong and durable design, allowing you to transfer power to your wheels with as little resistance as possible. The axle is made of steel and the bearings are well sealed. This makes this bottom bracket durable and low-maintenance!
SHIMANO - bottom bracket square type - MTB - standard structure
Bottom bracket with square axle
High-performance SHIMANO bottom bracket with square axle
Greater chainline stability with chainline stabiliser
3 structures available
Options: stand, E-type, chain guard
Bracket material: aluminium
Bottom bracket with square axle
High-performance SHIMANO bottom bracket with square axle
Greater chainline stability with chainline stabiliser
3 structures available
Options: stand, E-type, chain guard
Bracket material: aluminium
Ask a question about this product
Reviews
Reviews
Most recent reviews
1 / 5
Poor quality
- Erik 30 September 2026
This is the third bottom bracket on my three-year-old bike. The day after I replaced it, there was already a knock again… What I find strange is that it’s so cheap. I’d be happy to pay more for a more durable solution.
Pros & Cons
Ticks
Automatic translation
5 / 5
great product
- Martin 28 September 2026
The product is exactly as described, neatly packaged and delivered at the agreed time.
Pros & Cons
As described
User-friendly website
Very fast, complete delivery
None
Automatic translation
5 / 5
Excellent bottom bracket
- Dolf 10 September 2026
A good replacement for the old bottom bracket on my trekking bike. A square bottom bracket like that is quite heavy compared to the newer hollow models.
Pros & Cons
Excellent bottom bracket
Heavy
Automatic translation
4 / 5
You get what you pay for
- Rikkert 3 September 2026
After a year of fairly intensive use, there was quite a bit of play in the bearings. I’m not really used to Shimano bottom brackets,
Pros & Cons
Not expensive
Runs smoothly
Doesn’t last very long.
Automatic translation
4 / 5
Simple stuff, but so is the price
- Bram 7 May 2026
In daily use, this bottom bracket has lasted a year on me, but at this price, that is to be expected. Easy installation!
Pros & Cons
Cheap
Little durable quality
Automatic translation
Frequently bought together
Frequently bought together
Recommended by the product specialist
Recommended by the product specialist
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| Shimano BB-UN300 | Gazelle JIS 128mm BB | Sunrace BSA 68/122mm Steel | |
| 33 reviews | 1 review | ||
| Types Screw Thread | BSA | BSA | |
| Suitable for | Race / MTB | ||
| Size | 68 / 110 mm / 68 / 113 mm / 68 / 118 mm / 68 / 127 mm / 73 / 113 mm / 73 / 118 mm / 73 / 122 mm / 68 / 122 mm | 72 / 128 mm | |
| Crankset axle fit | Square Taper | Square Taper | Square Taper |
| Bottom bracket width | 68 mm / 73 mm | 72 mm | 68 / 122 mm |
| Bottom bracket diameter | 33.6-33.9 mm | 30 mm | |
| 76,30 | 89,80 | 58,30 | |
| This product | View product | View product |