Yamaha YF1-56942-39-30 - Crankshaft Metal (1ST U-S) is a genuine Yamaha part. This engine part is one of the internal components that keep the engine running as designed. Match part number YF1-56942-39-30 to the Yamaha parts diagram for your model to confirm it is the component you need.

---

Key Features & Benefits

• Replaces worn, scored, or damaged engine components.
• Installs in the position shown in the Yamaha engine parts diagram.
• Built to Yamaha's specification for its engine location.
• Size designation 1ST U-S as listed by Yamaha; confirm the required size with service manual measurements.

---

Frequently Asked Questions

What is the Yamaha Crankshaft Metal (1ST U-S) (YF1-56942-39-30)?

The Crankshaft Metal (1ST U-S) is a genuine Yamaha part sold under part number YF1-56942-39-30. It replaces a worn or damaged engine component with the specified Yamaha part.

What does the 1ST U-S size on part YF1-56942-39-30 mean?

O-S marks an oversize part and U-S an undersize part. Yamaha lists YF1-56942-39-30 as 1ST U-S, which is used when the mating part has been machined or worn to match. Measure and confirm the required size using the Yamaha service manual.

Should related parts be replaced with the Crankshaft Metal (1ST U-S), part YF1-56942-39-30?

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 YF1-56942-39-30.

---

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.