Yamaha - Gear 1 (21 Tooth) - Lower Unit Gear Component - 6CB-45561-00-00

Overview

When you’re dealing with lower unit issues, this is one of the gears that can make or break how the motor feels under load. Gear 1 handles a big part of the power transfer, and when it starts to wear, you’ll hear it and feel it right away. I’ve seen these cause everything from rough shifting to full-on slipping under throttle. Getting a fresh, properly machined gear back in place brings everything back to that solid, tight Yamaha feel.

Key Features

• 21-Tooth Gear Design – Maintains proper gear ratio for smooth and efficient power transfer.

• Precision Cut Teeth – Ensures clean engagement and reduces internal drivetrain wear.

• OEM Fit Accuracy – Matches Yamaha factory specifications for proper alignment and function.

• High Strength Construction – Built to handle torque, load, and harsh marine conditions.

Engine & Boat Compatibility

Verify compatibility with your specific Yamaha outboard model and part number before installation.

FAQs

Q1: What are signs this gear is worn out?
A: Grinding noise, slipping under load, or rough gear engagement.

Q2: Can I replace just this gear instead of the full set?
A: You can, but if other gears show wear, replacing the full set is usually the better move.

Q3: What causes this gear to fail?
A: Poor gear oil condition, heavy load use, or debris inside the lower unit.

Q4: Will this affect shifting performance?
A: Yes, worn gears can cause rough or inconsistent shifting.

Q5: Is this a difficult installation?
A: It requires full lower unit disassembly, so experience is important.