Yoshimura Spark Arrester Kit SA-08-K | Yoshimura RS-4 Muffler 1.375-Inch | USFS Approved

The Yoshimura Spark Arrester Kit SA-08-K is a USFS-approved 1.375-inch spark arrester insert for Yoshimura RS-4 mufflers, supplied with the spark arrester insert, end-cap collar and set screw.

An approved spark arrester is required in effectively every public off-road riding area in the United States — national forests, BLM land and organized OHV parks — and it is checked at the gate. Race-intent RS-4 systems ship without one, so this insert is what makes the machine legal for public land.

Size is the thing to get right. The RS-4 is offered with more than one outlet diameter, and an insert that does not match will not seal or retain correctly. This is the 1.375-inch version; measure your muffler outlet before ordering.

• USFS approved spark arrester insert
• 1.375-inch size, for Yoshimura RS-4 mufflers
• Kit includes spark arrester insert, end-cap collar and set screw
• Adds spark arrester capability to RS-4 systems not originally equipped with one
• Removable and refittable without muffler disassembly
• Yoshimura part number 961-9026 (manufacturer part SA-08-K)

Required equipment for riding Yoshimura RS-4 equipped motocross, enduro and off-road machines in US Forest Service areas, BLM land and organized OHV parks. Confirm your muffler outlet is the 1.375-inch size before ordering — the 1.50-inch RS-4 uses kit SA-04-K instead.