Legend Tuned · ECU Software
MotorcycleHarley-Davidson Fat Boy (Softail, 2025–) Milwaukee-Eight 117 Custom 106 HP ECU Software & Chip Tuning
- 2025–present
- Petrol
- 106 HP · 171 Nm
Target with Legend Tuned Stage 1: 113 HP / 181 Nm; with Stage 2: 120 HP / 189 Nm. The original software is backed up, the calibration is tailored to the car, and the result is verified by datalog.
Legend Tuned figures
Figures are examples/estimates and may vary with the car's mileage, maintenance condition, fuel quality and hardware. Exact results are determined by dyno/datalog.
Power & torque curve
Stock vs Stage comparison
A representative power and torque curve with a technical table of all figures. Hover over the chart to see values by rpm.
- Power · Stage 1
- Torque · Stage 1
- Power · Stock
- Torque · Stock
Technical figures
| Value | Stock | Stage 1 | Stage 2 |
|---|---|---|---|
| Power | 106 HP | 113 HP | 120 HP |
| Power (kW) | 78 kW | 83 kW | 88 kW |
| Torque | 171 Nm | 181 Nm | 189 Nm |
| Power gain | — | +7 HP (+7%) | +14 HP (+13%) |
| Torque gain | — | +10 Nm (+6%) | +18 Nm (+11%) |
Figures are examples/estimates and may vary with the car's mileage, maintenance condition, fuel quality and hardware. Exact results are determined by dyno/datalog.
Custom software · 6 options
Custom software options for this engine
Legend Tuned functions suitable for this engine, which can be applied in the same session as Stage software or on their own.
Emission Systems
Emission system solutions for track and motorsport projects.
- Catalytic Converter Delete (Cat Off) ECU software that prevents the check-engine light and power loss on cars with a removed or replaced catalytic converter.
- Rear Lambda/O2 Sensor Delete Software that turns off monitoring of the post-cat (rear) oxygen sensor to prevent the check-engine light on downpipe and sports cat setups.
Legal notice: Software for emission systems (catalytic converter, DPF/FAP, OPF, EGR, AdBlue/SCR, etc.) is intended solely for track / motorsport and closed-course use. Driving vehicles with these systems disabled on public roads, and presenting them for TÜVTÜRK inspection, may be against regulations. On request, the original software can be restored.
Driving & Sound Effects
Make yourself heard and be first off the line.
- Pops & Bangs (Crackle Map) Popular The signature pops and crackles from the exhaust when you lift off the throttle — intensity set to your taste.
- Rev Limiter Adjustment Software that re-sets the engine's maximum rev limit while staying within mechanical limits.
- Cold Start Idle Delete A software adjustment that reduces the high, noisy idle speed on a cold start.
Fault & Function Solutions
Permanent software fixes for annoying faults.
Stage 2 hardware, peace of mind and process
Stage 2 requirements
Stage 2 ready with exhaust and air filter
At Stage 2, the engine's breathing is freed up with hardware: the exhaust and air filter are upgraded, and the software is written to match that hardware. The target for this engine is 120 HP / 189 Nm.
- Exhaust systemA slip-on or full exhaust system; the software is written for the exhaust fitted.
- Air filterA high-flow sport air filter; the airbox inlet is modified if needed.
- Datalog & fine-tuningAir/fuel ratio and ignition are logged during a road or off-road test; fine-tuning is done if needed.
- Health checkIgnition, fuel system, clutch / CVT belt and cooling checked for this power level; the job takes ~4–8 hours (depending on parts fitted).
Included every time
Power with peace of mind
- Original software backup — the factory software is read and archived before the job.
- Reversal — the car can be returned to its original software whenever you ask.
- Datalog check — ignition, air/fuel ratio and engine temperature are recorded and checked during a road or off-road test.
- Vehicle-specific calibration — not an off-the-shelf file; tuned to the engine, hardware and fuel quality.
- Pre-tune diagnostics — fault memory is read and engine health is checked before the software.
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Book
Tell us about your car and your goals; we'll plan the day and time together.
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Analysis & backup
Fault memory is read, the ECU is identified and the original software is archived.
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Legend Tuned software
Calibration tailored to the car (Stage 1: ~1–2 hours).
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Test & handover
Verified with a road test + datalog, then handed over with a walkthrough of what was done.
Harley-Davidson Fat Boy (Softail, 2025–)
Other engines in the same generation
No other engines are listed for this generation.
Other Fat Boy generations
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