S&S CYCLE Crankcase Breather Reed Valve — +0.030" thread, Silver – 93-99 Touring, 93-99 Softail, 93-99 Dyna, 93-94 FXR, 99 CVO

The crankcase breather reed valve improves engine ventilation by opening when crankcase pressure exceeds cam chest pressure and closing when pressures equalize. ⚙️

• Reeds open on demand to reduce lag and prevent high‑rpm oil carryover in engines with marginal piston ring seal.
• By compensating for the mass of air being forced out of the crankcase, the valve increases performance and reduces oil carryover at high rpm.
• Installation is fast and simple — no timing marks to align and no rotating parts.
• Made in the USA.

Built for reliable operation under varying loads, this reed valve helps maintain optimal crankcase pressure to protect seals and reduce oil consumption.