Yamaha - Reed set - 6H4-W0004-00-00Yamaha Reed Set Intake System Component 6H4 W0004 00 00 Overview Reeds are one of those parts you dont see working, but you definitely feel when theyre not. Ive dealt with motors that just wouldnt idle clean or had a hesitation off throttle, and worn reeds were the culprit more than once. When they seal right, the engine breathes properly and runs smoother across the range. Its a small upgrade that can make a noticeable difference in how the motor