Table of Contents
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Performance Upgrades
Typical Staged Sportster Engine Upgrades 1)
Paying Taxes
Stage 0: Stock = HP- 40 for 883, HP- 50 for 1200 (average)
Stage 0.5 (also known as “The Harley Tax”)= HP- 50 for 883, HP- 60 for factory 1200 (Example)2)
- Stock plus:
- High flow air Cleaner OR
- SE Slip-On Mufflers or equivalent
Stage 1 Upgrades
Quote: Stage 1 and Harley Tax are synonims and include Pipes, Air Filter and Carburetor re-jetting/ ECU re-mapping 3)
- Stage 1.0 = HP- 60 for 883/1200, HP- 65-70 for factory 1200 (Example)4)
- High Flow Air Cleaner AND
- High Flow Exhaust AND
- Fuel/Air ratio adjustment : Jetting for carburetor, modify fuel tables in ecm with EFI bikes.
Known Stage 1 883 configurations
This is just examples of what has worked on some bikes. Each motor may be different in it's own unique way.
883 Engines:
- Carbureted / Year Model / Jetting / Mods:
- .
- .
- .
- .
- EFI:/ Year Model / Jetting / Mods:
- Screamin' Eagle Air Cleaner/ Screamin' Eagle Slip on exhaust
- .
- .
- .
- .
Known Stage 1 1200 configurations
1200 Engines:
- Carbureted / Year Model / Mods:
- EFI:/ Year Model / Mods:
Stage 1.5 Upgrades
Stage 1.5= HP-65 for 883/1200, HP- 70 for factory 1200 (Example)5)
- Stage 1 plus:
- Andrews N2 cams (mild)
Stage 2 Upgrades
Quote: Stage II: Stage I plus cam upgrades 6)
Quote: Stage II: Camshaft, Larger displacement, Higher compression 7)
- Stage 2: Stage 1.5 plus: (Example)8)
- Andrews N4, N8, or SE bolt-in cams instead of N2
- SE S1 Lightning or other bolt-on +/- 10:1 heads
- HP=75
- Options:
- 2 into 1 header system, add +/- 7 hp
- SE carb (or equivalent), add +/- 3 hp
- XR750 (or other) valve springs, no gain
- Stage 2.5: Stage 2 plus
- Professionally ported 10:1 or higher heads
- Matching (to head) domed pistons
- XR750 valve springs or SE cam kit
- 2 into 1 header system
- SE,S&S Super E, or Mikuni HSR42 carb
- HP=90+
- Options:
- big valves (big twin size), add +/- 5 hp
Stage 3 Upgrades
Quote:Stage III: Its on like Donkey Kong ! 9)
Quote: Stage III: Boring and/or Headwork and/or Forced Induction and/or Nitrous 10) Stage 3 = HP- ????
- Stage 2.5 plus:(Example)11)
- Big-bore cylinders and pistons and/or
- Stroker kit and/or
- Nitrous injection and/or
- Supercharging
- Options: many