Sumitomo Seal & Stainless Steel Piston Kit BC21Spss

Sumitomo Seal & Stainless Steel Piston Kit BC21SpssThis Brake Caliper Seal & Stainless Piston Kit includes the components necessary to rebuild the caliper(s) according to the specifications provided by the original manufacturer. Proper functioning of the brake system depends on pistons that move easily within the pistons and seals play a big role in protecting the pistons. Fluid leaks, reduced braking ability, unusual noises, or pulling to one side can all be signs that your caliper seals are bad.

This Brake Caliper Seal & Stainless Piston Kit includes the components necessary to rebuild the caliper(s) according to the specifications provided by the original manufacturer. Proper functioning of the brake system depends on pistons that move easily within the pistons and seals play a big role in protecting the pistons. Fluid leaks, reduced braking ability, unusual noises, or pulling to one side can all be signs that your caliper seals are bad. Please contact us with questions regarding fitment.

These replacement pistons are made from high-grade 316L stainless steel, known for its exceptional durability and resistance to rust and corrosion—even in tough conditions. They're a long-lasting upgrade over standard parts and are built to handle heat and wear better than common stainless steels like 303 or 304.

This kit is fitment specific. Please consult the fitment table to confirm that it fits your motorcycle before purchasing. This kit has replacement seals & pistons based on the fitment specifications for each motorcycle listed.  

For a complete list of what this kit includes check the Product Includes tab above.

We include our red rubber grease specially designed for brake projects, providing lubrication for assembly, protect from dry burn, and prevent swelling and hardening of rubber hydraulic component seals.

Important Safety Disclaimer – Brake Parts Fitment Installation: Before purchase or installation, it is your responsibility to confirm that your bike model is listed in the product ’s fitment table. Incorrect fitment can cause serious safety risks. If you're unsure or need a hand, we’re here to help —just reach out and we’ll gladly assist you in confirming compatibility.

Brake components are critical to safety and must be installed by a certified mechanic. Improper installation can lead to brake failure, injury, or death. By purchasing, you accept full responsibility. While we’re always happy to support you with guidance, we cannot be held liable for any issues resulting from incorrect installation or use.