Yamaha BYS-E5121-00-00 - Crankcase 2 is a genuine Yamaha part. This engine part is one of the internal components that keep the engine running as designed. Match part number BYS-E5121-00-00 to the Yamaha parts diagram for your model to confirm it is the component you need.

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Key Features & Benefits

• Built to Yamaha's specification for its engine location.
• Replaces worn, scored, or damaged engine components.
• Installs in the position shown in the Yamaha engine parts diagram.
• The 2 in the name separates this part from others that share the same name, so order by part number BYS-E5121-00-00.
• Sold under Yamaha part number BYS-E5121-00-00.

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Frequently Asked Questions

What is Yamaha part BYS-E5121-00-00?

BYS-E5121-00-00 is the Yamaha part number for the Crankcase 2, a genuine Yamaha part. It replaces a worn or damaged engine component with the specified Yamaha part.

Why is there a 2 in the name Crankcase 2 (BYS-E5121-00-00)?

Yamaha adds numbers to parts that share a name so each one can be told apart. The 2 does not indicate quantity, so order by the full part number BYS-E5121-00-00 rather than by name.

Should related parts be replaced with the Crankcase 2 (BYS-E5121-00-00)?

When replacing engine internals, inspect mating parts and replace gaskets and seals disturbed during disassembly. Refer to the Yamaha service manual for your model when installing BYS-E5121-00-00.

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WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.