Standard Size Breather Gear Kit For Big Twin

S&S steel rotary gear kit. • Steel breather gears have better dimensional stability than plastic gears, Steel breather gears have better dimensional stability than plastic gears, imbedded in a steel gear body. Embedded particles can damage the crankcase breather gear cavity. • A screen provides better protection than a slotted gear– small particles are stopped from getting to the gear cavity where they may damage the gears and oil pump. • S&S steel gear with welded in screen with larger diameter holes provides improved air flow/oil scavenging from the flywheel cavity. • Crankcase flywheel cavity vacuum and oil scavenging are further improved by optimized breather window timing. Breather oil trap scavenging is significantly improved by increased scavenge port duration. These improvements are the result of exhaustive research using digital sampling and data acquisition equipment. • Standard size for late 1977 – ’99 Harley-Davidson® big twins. • Breather gear kits include breather gear and steel end play shim kit.