Sunlite Bottom Bracket Conversion Kit

This kit allows you to install a modern three-piece crankset onto an older bicycle frame that originally used an American-style (one-piece) bottom bracket. It essentially bridges the gap between vintage frame standards and modern drivetrain components.

This kit is designed specifically for frames with a standard 68mm American bottom bracket shell. If your frame has a different shell width or a non-standard interface, this kit will not be compatible.

You will need to pair this with a three-piece crankset that utilizes a JIS square taper interface. This is a very common standard for many mid-range and vintage-style cranksets.

Yes, this is a complete conversion kit. It includes the necessary bearings, cups, and the 130mm JIS square taper spindle, providing everything you need to make the switch in one package.

While the steel construction is durable and reliable for general riding, commuting, or light trail use, it is primarily intended for refurbishing vintage frames or standard upgrades. If you are building a high-performance mountain bike or a heavy-duty touring rig, you may want to look for sealed cartridge bearing options.