ThunderMax PN#309-588 Applications:
• 2017 - 2018 Touring® Models - Air & Twin Cooled (Throttle-by-Wire)
• 2017 - 2018 Touring® Trike Models - Air & Twin Cooled (Throttle-by-Wire)

ThunderMax is an industry award winning, performance ECM designed specifically for EFI equipped Harley Davidson® motorcycles. This highly advanced, stand-alone tuning system utilizes proprietary AutoTune technology with wide-band oxygen sensors to deliver unmatched performance and rideability. ThunderMax comes 100% assembled, ready to install with no wire-cutting or splicing required. Simply replace the factory ECM and oxygen sensors, load a map, and enjoy your new ride!



ThunderMax Benefits Include:
  • Easy to Install & Simple to Use
  • Increased Engine Performance & Motorcycle Rideability
  • Cooler, Smoother Running Engine
  • Adjustable Idle Speed & Rev Limit Control
  • No Dyno Required - Automatically Tunes for Riding Style & Riding Conditions
  • Never Outgrow It - Easily Accomodates Bike Changes (Pipes, Cams, and More)
  • 100% Engineered & Made in the USA
  • 3-Year Factory Limited Warranty

ThunderMax System Includes:

  • ThunderMax Performance Engine Control Module (ECM)
  • Two (2) Wide-Band Bosch 5-Wire Oxygen Sensors (18mm) with AutoTune Connection Harness*
  • USB Communication Cable
  • TMax Tuner Software Disc
  • ThunderMax Quick Start Easy Install and Printable Comprehensive User’s Manual



Year Make Model
2017 - 2018 Harley-Davidson Electra Glide Ultra Classic (EFI) - FLHTCU
2017 - 2018 Harley-Davidson Electra Glide Ultra Limited - FLHTK
2017 - 2018 Harley-Davidson Freewheeler-FLRT
2017 - 2018 Harley-Davidson Road Glide Custom - FLTRX
2017 - 2018 Harley-Davidson Road Glide Special - FLTRXS
2017 - 2018 Harley-Davidson Road Glide Ultra - FLTRU
2017 - 2018 Harley-Davidson Road King (EFI) - FLHR
2018 Harley-Davidson Road King Special - FLHRXS
2017 - 2018 Harley-Davidson Street Glide (EFI) - FLHX
2017 - 2018 Harley-Davidson Street Glide Special - FLHXS
2017 - 2018 Harley-Davidson Tri Glide Ultra Classic - FLHTCUTG
2017 - 2018 Harley-Davidson Ultra Limited Low - FLHTKL

This product is intended for "RACE READY" vehicles only and is not for sale or use on vehicles otherwise subject to emission control requirements.  In the state of California, this product should not be used on any vehicle that is registered for use on public roads. Please view the ThunderMax 50 application guide for "STREET APPROVED" & ARB compliant products.

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