KTM Performance guide
Technical Reference Guide
Performance Mods Guide
KTM · Husqvarna · GASGAS Enduro · Intake, Exhaust & ECU · Real Dyno Numbers
CLOSED COURSE COMPETITION USE ONLY. Removing or modifying any sound or emissions control system makes a vehicle illegal on public roadways. Not CARB/EPA compliant. Modify at your own risk. Early 2025 draft — numbers subject to change.
Bikes Covered
KTM 350/500 EXC-F (2020+)
KTM XCF-W / XW-F (2020+)
Husqvarna FE / FEs 350/501 (2020+)
GASGAS ES / EW 350/500 (2024+)
Real Dyno Numbers — Taco Moto Dynojet 168 Series
What These Bikes Actually Make
KTM
2025 350 EXC-F
2,300 ft • 74F • Slick rear / 30 psi
Stock
36.4 hp
Modified
47.6 hp
+11.2 hp — 31% gain at the wheel
KTM
2025 500 EXC-F
2,300 ft • 77F • Slick rear / 30 psi
Stock
38.2 hp
Modified
59.7 hp
+21.5 hp — 56% gain at the wheel
01 — Intake System
✓ Taco Moto Recommends
Intake Reed Removal
Pros
- +More mid and top-end power
- +Eliminates failure point — carbon fiber petals documented to break off and damage valves
- +Eliminates risk of reeds popping backwards and cutting airflow
- +Free
Cons
- −Reduces some low-end torque and smoothness
- −Increases intake sound
- −Leans out AFR — fuel correction required
✓ Taco Moto Recommends
Vapor Recovery Delete
Pros
- +Removes failure and maintenance points
- +Slight weight savings
- +Free to low-cost
Cons
- −No power effect whatsoever
- −Increased fuel vapor smell in enclosed trailers and vans
✗ Do NOT Recommend
Intake Velocity Stack
Internet myth that the air boot collapses without reeds — it doesn't. Our dyno showed 2–8hp power loss across the powerband.
Pros
- +None measurable
Cons
- −Unnecessary cost
- −2–8hp power loss on our dyno
02 — Exhaust System
✓ Good Starting Point
Stock End Cap Mod
Restricts airflow 33% with a 26mm outlet. Cut the restriction, knock out the plug.
Pros
- +Full powerband airflow gain
- +Engine runs cooler and more efficiently
- +Retains stock look • Free
Cons
- −Louder
- −If done wrong, voids spark arrestor compliance
- −26mm limits full power potential
- −Fuel correction required
★ Best Value Pick
Pro Moto Billet End Cap
Pros
- +42mm outlet — full power potential extracted
- +Engine runs cooler and more efficiently
- +Optional ultra-silent insert available
Cons
- −Louder
- −Fuel correction required
.
Stock Cone Resonator Removal
Best for fast open-terrain riders. Not ideal for technical enduro.
Pros
- +Mid to top-end power increase • Free
Cons
- −Kills bottom-end torque
- −Annoying engine drone
- −Difficult to remove
- −Fuel correction required
.
FMF 4.1 Slip-On
Loud and punchy. Best for supermoto, snow bike, desert. Not for technical enduro.
Pros
- +Full powerband airflow gain
- +Hard-hitting punchy power
- +Up to 1.1 lb weight savings
Cons
- −Very loud
- −Snappy harsh low-end — not for technical terrain
- −May melt turn signal • Fragile carbon end cap
- −Fuel correction required
★ Best All-Around Pick
Graves Muffler
Pros
- +Strong, smooth power full rev range
- +Removable DB killer / spark arrestor included
- +Up to 1.3 lb weight savings
- +Best all-around for all riding styles
Cons
- −Louder
- −Cost • Fragile carbon end cap
- −Fuel correction required
.
Yoshimura Muffler / Full System
Pros
- +Strong, smooth power full rev range
- +Removable DB killer / spark arrestor
- +Suits all riding levels
Cons
- −Quite loud • Nearly stock weight
- −May melt turn signal • Fragile carbon end cap
- −Fuel correction required
03 — ECU, Tuners & Mapping
The narrow-band O2 sensor only trims AFR in the cruise zone (14.5–16.5). It cannot reach the 13–14 range for safe best power. With open exhaust and reeds removed we have logged AFR in the upper 17s on a stock ECU. Dangerously lean. Fuel correction is not optional — it is required.
★ Best Overall — GET SX1
GET SX1 Race ECU
Best performing and best equipped ECU available. Buy from Taco Moto: lifetime map + hardware warranty.
Pros
- +Fuel and ignition — maximum power
- +Race and singletrack maps
- +10-mode traction control, overheat warning, launch control via LED switch
- +WiFi smartphone app tuning
- +Built-in baro sensor — auto elevation compensation
- +OBD2 enabled • Lifetime warranty from Taco Moto
Cons
- −Premium cost
★ Taco Moto — Ship-In Reflash
TacoFlash — Stock ECU Reflash
Pros
- +Best bang for the dollar
- +Adjusts fuel AND ignition
- +OBD2 enabled
- +No added hardware — retains stock Keihin ECU
- +Optional map switch: dual maps, quick shift, TC (2024+ bikes) $169
- +Lifetime Taco Moto map support
Cons
- −No user-adjustable fuel or ignition trim
- −Must ship ECU back for map changes
★ Taco Moto — Flash at Home
TacoFlash — Power Vision 3
Pros
- +Flash at home — no shipping needed
- +Adjusts fuel AND ignition
- +OBD2 scan/diagnostic tool
- +PV device works on other bikes, street bikes, UTVs
- +Optional map switch: dual maps, quick shift, TC (2024+ bikes) $169
- +Retains stock ECU • Lifetime map support
Cons
- −✓ None listed
.
Vortex Race ECU
Pros
- +Best known aftermarket ECU
- +Fuel and ignition — max power
- +Multiple maps including singletrack
- +Single-mode TC on some models
- +Fuel trims via rotary dials • Launch control • Quick shift
Cons
- −Cost — especially with software and cable
.
AIM Race ECU
Least known but strong value. Early units had reliability issues.
Pros
- +Fuel and ignition — max power
- +Multiple maps including singletrack
- +Five-mode TC via LED switch
- +Free software + low-cost cable
- +SOLO 2 data logging + live AFR available
Cons
- −Early unit reliability issues documented
.
Dobeck EJK Piggyback Tuner
Pros
- +Low cost • Easy install
- +User-adjustable fuel trims via onboard buttons
- +Smooth, warm linear power
- +Can be bypassed if unit fails
Cons
- −No ignition timing adjustment
- −No singletrack map
- −Modest gains vs. other options
- −Adds hardware to bike
.
Dynojet Power Commander
Pros
- +User-adjustable with free Dynojet software
- +Custom tune at hundreds of Dynojet shops nationwide
- +Autotune with wideband O2 available
- +Quick shift and economy map switch available
- +Very clean, accurate fueling • Bypasses if fails
Cons
- −No ignition timing adjustment
- −No singletrack map capability
- −Adds hardware to bike
✓ Free Tips
No-Cost Stall Fixes
+Run idle speed +200 rpm over spec — most effective single fix
+Ride in a lower gear — keeps RPMs in a more stable zone
+Run a lower gear ratio — sprocket swap
+Improve clutch management — free and always available
Taco Moto Dynojet 168
HP Racing Partnership
Athena GET Factory Tuning
Real-World Test Riders
Lifetime Map Support