Dyna Harley Davidson Screamin' Eagle
The decision most buyers actually have to make here isn't which part looks best. It's which Stage kit matches the engine they already have, and what that pulls in behind it.
Stage kits are matched to an engine size, not a model name
On the Milwaukee-Eight alone there are separate Stage IV kits for taking a 107 up to 114 cubic inches (92500062), a 114 or 117 up to 131 (92500080), and a 107 all the way to 128 (92500077) — three boxes carrying the same name, told apart only by the engine you're starting from. The Twin Cam line has its own Stage III kit, topping out at 103 to 110 cubic inches (92500035), a different range again. The standalone Stage inserts (25600118 to 25600129) are stamped with both a stage number and a cubic-inch figure for the same reason. Buy by CI, not by Stage name alone.
Fitment traps hide in parts that look identical
The clearest case is the ignition wires. "10mm Phat Spark Plug Wires" is one product name sold in at least seven separate fitments on this shelf: a '99 to '17 Dyna needs one set (31937-99C), an older Twin Cam Dyna or '80s Touring bike needs another (31964-89C), and a '09 to '16 Touring or Trike needs a third (32318-08A). None of them interchange. Order by name rather than by year and model, and you will get the wrong one.
The tune, and the extras that don't come in the box
Harley-Davidson's own listing for the Milwaukee-Eight Stage II Power Kit (92500075A) is direct about it: "all models require ECM calibration with Screamin' Eagle Pro Street Tuner for proper installation." The same page lists a separate Cam Drive Retention Kit as required, and an Oil Pump Cover as recommended on '17 to '18 Touring bikes. Neither is in the kit's own box. Not everything on this shelf needs a tune on its own; a slip-on muffler is a different job to a full engine kit. Check the specific listing, or ask us, before you assume either way.
Screamin' Eagle also covers suspension and one very specific clutch. Öhlins-tuned rear shocks (54000350, 54000384, 54000325) sit on the same shelf as the Stage kits, and the slipper clutch built for VRSC models (37938-08KA) fits the old liquid-cooled V-Rod line, discontinued in 2017 and mechanically unlike anything else here. If you're fitting one of the Street Cannon exhaust kits (64900555A, 64900638, 64900554B) for road use, the DVSA's MOT test carries no decibel figure: it fails an exhaust judged unreasonably louder than a standard system, checked warm at around half maximum revs. Ask before you fit one, not after your first MOT.
Whether a particular kit affects your warranty is also worth raising with us before you order, not after. These are genuine Harley-Davidson Screamin' Eagle parts, for sale with 10% off RRP and free UK delivery available, and the parts desk can talk you through fitment before you buy. For anything Screamin' Eagle doesn't cover, the rest of our Harley-Davidson parts range is next door.