BB-UN300-K Bottom Bracket - English 68 x 117.5mm Spindle Square Taper JIS For Chain Case

The Shimano BB-UN300-K bottom bracket is a top - notch choice for your bike. It's designed with an English 68mm bottom bracket shell and a 117.5mm JIS square - taper spindle, specifically made for chain cases. This bottom bracket fits JIS square - taper cranksets. The crankarm fixing bolts are sold separately. Its hollow spindle design not only saves weight but also offers good strength. It comes in a sleek black color. Technical specs include a 1.37 bottom bracket shell inner diameter and an English BB/frame interface.

Using this Shimano BB - UN300 - K bottom bracket is straightforward. First, make sure your bike's bottom bracket shell matches the English 68mm size and the JIS square - taper spindle type. When installing, be careful not to overtighten the bolts. Since the crankarm fixing bolts are sold separately, buy the right ones for a proper fit. During use, keep an eye on the smoothness of the rotation. If you notice any unusual noise or resistance, it might need attention. For maintenance, regularly clean the bottom bracket to prevent dirt and grime from building up. You can use a mild bike cleaner and a soft brush. After cleaning, dry it thoroughly. Lubricate the moving parts occasionally to ensure long - lasting performance.