This 43mm throttle body assembly is intended for KTM 250 TPi, KTM 300 TPi and model year 2017 onwards BRC500 applications, where it increases airflow and repositions the injectors to deliver fuel at an improved angle. In practical use, it is designed to improve throttle response, power output, starting, bottom-end lubrication and running temperature control, while also giving cleaner routing for engine bay wiring and fuel lines. Safe operation requires a TSP reflash or GET ECU, and installation requires selected parts from the original throttle body to be transferred to the new assembly.

Features

• Improved throttle response
• Increased power output
• Improved bottom-end lubrication
• Lower running temperatures
• Easier starting
• Injector relocation for cleaner engine bay wiring
• Injector relocation for neater fuel line routing
• Designed to match reed valve flow
• Supports pre-mix operation

Specifications

• Throttle body diameter: 43mm
• Baseline idle air screw setting after installation: 3.5 turns out from fully seated

Kit Contents

• Larger throttle plate
• Injector port plugs
• O-rings
• Two injector harness extension cables for applications requiring additional injector lead length

Installation Notes

• OEM fuel rail and cylinder-mounted injectors are removed during installation
• Cylinder injector ports must be sealed using the supplied injector port plugs and O-rings
• The original fuel injectors are reused and installed into the throttle body assembly
• The tank-to-fuel-rail quick-disconnect section from the original fuel hose is reused
• OEM throttle position sensor, cold-start plunger, idle air screw, throttle shaft and throttle-shaft seals are transferred from the original throttle body
• The stock throttle-shaft butterfly slot must be enlarged to accept the supplied larger throttle plate
• For 2017 to 2019 KTM models, later-model KTM idle screw and cold-start plunger/button are required

Cross-Reference OEM Part Numbers

• KTM idle screw: 55741060000
• KTM cold-start plunger/button: 55741070000

Vehicle Fitments

• KTM 250 TPi, all TPi models
• KTM 300 TPi, all TPi models
• BRC500, model year 2017 onwards