HUSQVARNA jet

HUSQVARNA jet

The HUSQVARNA jet needle (S-1) is a carburetor fuel metering component for Husqvarna/KTM/GasGas 2-stroke engines using Keihin carburetors, identified by OEM part number 55431021100. This needle jet helps control mixture strength across the throttle range on many KTM, Husqvarna Motorcycles, and GasGas 125–300 off-road models.

Technical specifications

• Part type: Needle jet
• System: Carburetor fuel metering component
• OEM designation: S-1 needle jet
• OEM part number: 55431021100
• Associated applications: 2-stroke off-road motorcycles with Keihin carburetors (various KTM/Husqvarna Motorcycles/GasGas 125–300 models)
• OEM usage: Shared part number across KTM, Husqvarna Motorcycles, and GasGas parts catalogs

Use context

Use this HUSQVARNA jet when restoring stock fueling, correcting wear in the carburetor metering circuit, or returning to OEM specifications after jetting changes. It is commonly replaced together with main jets, pilot jets, and needle assemblies to restore consistent fueling.

Installation

The needle jet installs directly into the Keihin carburetor body as an OEM replacement; verify part number 55431021100 against the motorcycle’s parts fiche and follow the workshop manual for disassembly, orientation, and torque where applicable.