Stage 1 Air Cleaner Comparison.
For Milwaukee-Eight Touring and Softail owners — the top six kits, sorted by year-fitment and by what you actually feel when you twist the throttle.
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A Stage 1 air cleaner is the other half of the classic M8 power package: it replaces the restrictive stock airbox, exposes the breather re-circulation, and lets the Milwaukee-Eight breathe. Arlen Ness and S&S Cycle dominate this space for good reason — filter media quality, hidden breather systems, and fitment across the 2017–2022 M8 and the 2023-up Gen-2 engines. Here is how the six listed kits compare.
What Actually Matters
- Engine generation. 2023-up Gen-2 M8 Touring kits (Arlen Ness "23-26 G2" line) differ from 2017–2022 M8 kits. Match your year.
- Breather design. Hidden/internal breather kits route blow-by internally — cleaner look, no oily film on your leg; Arlen Ness Big Suckers add a built-in oil reservoir to catch blow-back, a frequent owner-praise point on M8 forums.
- Filter media. Cotton gauze (oiled, reusable) is the default; synthetic and stainless-jacket options cost more but handle wet weather and extended service intervals better.
- Cover style and price. The same kit body often spans $179–$319 depending on cover (plain, Beveled, 10-Gauge, Knuckle, carbon).
- Tuning. A Stage 1 air cleaner alone usually runs acceptably; combined with slip-ons, add a fuel manager for best results.
Comparison: M8 Stage 1 Kits
| Kit | Best for | Fitment | Price | Rating | Retailer |
|---|---|---|---|---|---|
| Arlen Ness Big Sucker 50-330 | Best value Stage 1 | M8 / big twin (check year) | $179.95 | ★4.8 | Dennis Kirk |
| S&S Super Stock Stealth | Budget stealth look | M8 models | $176.36 | ★4.8 | TC Bros. |
| Arlen Ness Big Sucker (G2) | 2023–2026 Gen-2 M8 Touring | 23-26 G2 M8 Touring | $199.95 | ★4.7 | Arlen Ness |
| Arlen Ness Big Sucker Wedge | 2017–2025 Softail/Trike/Touring | 2017–2025 M8 | $209.95 | ★4.8 | TC Bros. |
| S&S Stealth Air Stinger 170-0714A | Best mid-price performance | Milwaukee-Eight | $249.95 | ★4.9 | Fuel Moto USA |
| S&S Tuned Induction | Premium show + go | M8 Touring | $595.95 | ★4.7 | RevZilla |
Our Picks
- Best value: Arlen Ness Big Sucker 50-330 — $179.95 (Dennis Kirk, ★4.8). The proven Stage 1 benchmark with cover included. Check price at Dennis Kirk →
- Best for 2023–2026 Gen-2 M8: Arlen Ness Big Sucker G2 — $199.95 (Arlen Ness, ★4.7). Purpose-built for the newest Touring engines. Check price at Arlen Ness →
- Best for 2017–2025 Softail + Touring: Arlen Ness Big Sucker Wedge — $209.95 (TC Bros., ★4.8). One kit spanning Softail, Trike and Touring M8s. Check price at TC Bros. →
- Best mid-price performance: S&S Stealth Air Stinger — $249.95 (Fuel Moto USA, ★4.9). A well-rated kit in the source comparison. Check price at Fuel Moto →
- Premium: S&S Tuned Induction — $595.95 (RevZilla, ★4.7). Maximum airflow and show-quality finish. Check price at RevZilla →
⚠ Fitment warning: Do not buy a 2023-up Gen-2 kit for a 2017–2022 M8 or vice versa without confirming — the throttle-body and breather hardware changed. Match the exact year range on the product page and confirm against your VIN.
FAQ
How much horsepower does a Stage 1 air cleaner add?Typically 3–5 hp with a full Stage 1 (air cleaner + exhaust + tune); the air cleaner alone adds less.
Do I need a tuner?Not always for the air cleaner alone, but strongly recommended once combined with free-flowing exhaust.
Why do M8 owners prefer Arlen Ness Big Suckers?The built-in oil reservoir catches engine blow-back that would otherwise coat the bike — a recurring theme in M8 forum discussions.
Are the filters washable?Cotton gauze filters are oiled and reusable with filter oil; follow the manufacturer's service interval.
Will a Stage 1 kit void my warranty?Emissions-related parts are protected under Magnuson-Moss; document your install and confirm with your dealer.