FB vs. BS Finished Bore Sprockets

Here at MDS of Michigan, we understand that sprockets are an integral component of many mechanical systems, serving the crucial role of transferring motion and power from one part to another. When it comes to sprockets, you might have come across different bore nomenclatures like “FB” and “BS” finished bore sprockets. At first glance, they might seem like distinct products, but in reality, they refer to the same type of sprocket.

FB vs BS Finished Bore Sprockets: Different Labels, Same Product

FB and BS finished bore sprockets are, in essence, identical in terms of design and functionality. The only difference lies in the terminology used by different manufacturers. Some manufacturers prefer to label their sprockets as “FB,” while others opt for “BS.”

  • FB stands for – Finished Bore
  • BS stands for – Bore to Size

Each manufacturer has its own way of referring to finished bore sprockets, which can be influenced by factors such as location, tradition, or branding strategies. For example, a manufacturer based in the United States might prefer the term “FB” or even “B,” while one from Europe could use “BS.” This is not unlike regional variations in other industries, where different terms may be used to describe the same product.

When you encounter an FB finished bore sprocket from one manufacturer and a BS finished bore sprocket from another, you can rest assured that both products are intended for the same purpose. They are sprockets with a finished bore, which means that they come with a pre-machined hole in the center to fit onto a shaft or hub. The bore size is typically specified in inches or millimeters, allowing you to choose the sprocket that matches your shaft’s dimensions.


Do not get bogged down by nomenclature; we have got the perfect sprockets to suit your needs. Whether you are after “FB” or “BS” finished bore sprockets, we have got them all.

Visit our online store today and experience the ease of finding precisely what you need. Do not miss out – upgrade your system with MDS of Michigan’s finished bore sprockets now!

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