The slide restrictor is the piece inside your Briggs LO206 carburetor's slide assembly that physically limits how far the throttle can open, capping airflow (and power) below the engine's unrestricted output. Sanctioning bodies specify different restrictor sizes by class so younger and entry-level classes run a detuned, safer power level. Common sizes:
- Black .310 — Kid Kart (P/N: 555732)
- Green .490 — Cadet (P/N: 555740)
- Yellow .570 — Jr (P/N: 555741)
