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⚙️ Ride Smooth, Ride Sharp – Upgrade Your Pedal Game Today!
The Shimano UN300 English Bottom Bracket is a high-quality, sealed bottom bracket designed for JIS square taper cranksets. Featuring a 68mm shell width and a 113mm hollow spindle, it offers precise fit and enhanced chain reliability thanks to its chain line stabilizer. Constructed from durable aluminum alloy, it comes in multiple size options to suit various bike configurations, making it a trusted choice for cyclists seeking smooth, efficient performance.
| ASIN | B08BX7TJPP |
| Best Sellers Rank | #81,543 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #15 in Bike Bottom Brackets |
| Brand Name | SHIMANO |
| Color | noir/argentà |
| Customer Reviews | 4.6 4.6 out of 5 stars (309) |
| Date First Available | June 26, 2020 |
| Included Components | Bottom Brackets |
| Item Dimensions LxWxH | 5.63 x 2.03 x 1.91 inches |
| Item Package Dimensions L x W x H | 7.2 x 5.59 x 1.73 inches |
| Item Weight | 0.01 Ounces |
| Manufacturer | Shimano |
| Material | Alloy |
| Model Name | Bottom Bracket - English, 68 X 113mm |
| Number of Items | 1 |
| Package Weight | 0.29 Kilograms |
| Part Number | EBBUN300B13X |
| Size | 68mmx113mm |
| Sport Type | Cycling |
| Style | Bottom Bracket - English, 68 X 113mm |
| Suggested Users | unisex |
| Warranty Description | Limited Warranty |
M**K
Cheap Fun
Smooth, zero slop, exact fit, easy to install!
M**.
Works great. Shimano is the best!
Requires socket designed specifically for bottom bracket installation, sold separately.
M**S
Perfect fit!
Went in with no fuss and is silent as can be. No telling on longevity, but the previous one lasted twenty years of hard, off-road use and was still technically function, just squeaky. Was a fun job, first time doing it myself. Much easier than I imagined and was great to save the $$ vs a shop visit.
B**N
Affordable sealed bb bearing...
Way to go for replacing cheap department store cranksets.
T**N
Good old standard square taper Shimano bottom bracket
Made a "new" bike using an old frame. I'm glad there's still some parts that Shimanos continues to make , like bottom brackets for square taper standards. The Shimano UN-300 bottom bracket is 68/73 width, was easy to install, and smooth bearings. Will last for years and years.
M**G
Great for trek
Perfect repair for my Trek 8.3 DS.
R**C
Piece of cake!
The BB on my 1996 Giant mountain bike wasn't bad but I felt like doing some maintenance and upgrades. After following some Youtube videos, I felt confident enough to change the old one with this new one. If you don't have one, you'll need a crank arm puller which isn't that expensive but necessary to have. Luckily, none of the threads were frozen so removal was rather easy. After cleaning out the BB shell, reassembly was straightforward and easy. The whole project took about 45 minutes. When everything was buttoned up, I took the bike for a test ride. I was impressed by how smoothly the crank turned and the bike seemed to have a new life. You'll need some grease for the threads plus a 20-tooth spline to unscrew/re-tighten the cups.
W**N
Best BB because of cartridge bearings
This BB has cartridge bearings which are much better than a BB assembled with ball bearings and races on the shaft and housing. This BB-UN300 is a direct replacement for a BB-UN73. Be sure to use anti-seize on aluminum and steel threads. The sleeve has thread-locker so placement of the anti-seize has to be carefully applied to prevent contamination of the thread-locker.
A**R
Fit and working perfectly
M**E
La bici se siente un movimiento suave y ligero al pedalear con este eje y es ligero. Fácil de instalar, si se tiene la herramienta adecuada para ello
Trustpilot
3 days ago
2 weeks ago