Engine

Active filters
Enhances the center of the oil cooler trim with a stylish guard. Easy to install and built in the USA.
Dresses up the oil cooler area with matching vent‑screen material; easy to install. Made in the USA.
Includes top and second compression rings plus three-piece oil control rings; supplies enough rings for two pistons for reliable sealing and oil control.
Complete replacement ring set with top and second compression rings plus three-piece oil control rings. Restores compression, controls oil, and improves oil economy. Includes enough rings for two pistons. Made in the USA.
Complete set of top, second, and three-piece oil control rings for two pistons. Barrel face top rings and Napier second rings provide improved sealing and heat transfer; three-piece Flex Vent oil rings ensure positive oil control. Made in the USA.
Complete replacement piston ring set with PVD coating: barrel face top rings, Napier second rings, and three‑piece flex vent oil control rings. Includes enough rings for two pistons.
Steel-base, one-piece crankcase vent filters. 50.8 mm (2") diameter; 38.1 mm (1½") height. Available with or without mounting stud.
State-of-the-art compression release valves that reduce hot starts and lower starter and battery loads. Sold as a set and made in the U.S.A.
State-of-the-art design to reduce hot starts and starter/battery loads. Custom molded knobs, sold in pairs, made in the U.S.A.
Complete mounting kit with all required hardware for inner primary installation. Made in the USA.
Plug and plug kits for various Harley‑Davidson oil systems; includes washers or O‑rings as required. Made in the U.S.A.
Heat-treated, plated adjuster bolts with included chrome lock nuts. Made in the USA.
Durable button-head Allen drain screws with copper compression washers for fork sliders.
Stem bolt with washer; complete hardware kit, made in the U.S.A.