970810 Steel breather valve. std

Keeping the crankcase pressure in check is vital on vintage Knuckleheads and early Flatheads, and this standard steel breather valve is a faithful OEM-style replacement. It fits 1936 to 1947 Big Twin models and is manufactured to the original specifications to ensure proper timing of the breathing cycle. A worn breather valve can lead to oil leaks and poor scavenging, so replacing it during a bottom-end rebuild is highly recommended. This part corresponds to OEM numbers 25300-36 and 970810, providing the reliability and fitment you expect when maintaining or restoring a classic Harley-Davidson powerplant.