KTM 790 & 890 Adventure Air Filter Guide
The short answer, up front: FunnelWeb makes a complete washable foam filtration system for the KTM 790 Adventure, 890 Adventure, and Husqvarna Norden 901, which share the same airbox design. Five options cover it: the Full Kit (7336, $159.90) with main filter, FWF frame, and pre-filter plugs; the Main Filter with Frame (7339, $99.95); the Spare Main Filter (7338, $39.95); the Pre-Filter Plugs, set of 2 (7337, $59.95); and the Rottweiler Performance Replacement Filter (7340, $47.94) for bikes running that intake. All of them use pyramid profile-cut foam with twice the external surface area of a standard filter.
Why the 790/890 needs this
The LC8c platform is a genuinely great adventure bike with one well-known weak point: the stock air filter. Questionable seal, poor dust filtration, and a short service life. Owners who ride real dirt find fine dust past the filter and inside the airbox, and fine dust is exactly what wears rings and valves. On long rides like a BDR or a Trans America Trail run, filtration is not a detail. It is the thing keeping the engine alive.
The FunnelWeb approach replaces the stock filter and cage with an oiled foam element mounted on the FWF frame, sealing properly against the airbox and trapping dust through the full depth of the foam. The pyramid surface doubles the external surface area without changing the size, so the filter holds roughly twice the dust before airflow drops.
The five options, explained
Full Kit (7336)
Main filter, FWF frame, and both pre-filter plugs in one order. The complete system and the best value at $159.90. This is the setup for riders who see regular dust.
Main Filter with Frame (7339)
The core upgrade at $99.95: the pyramid foam main filter mounted on the FWF frame, replacing the stock filter and cage. Everything else builds on this.
Spare Main Filter (7338)
A replacement foam element at $39.95 for riders who already own the FWF frame. Keep a pre-oiled spare in a sealed bag and filter service on a trip becomes a five minute swap. Note: it requires the FWF frame and does not fit the stock cage.
Pre-Filter Plugs (7337)
A set of two oiled foam plugs at $59.95 that fit the intake openings and stop heavy dust before it reaches the main filter. The cheapest insurance on the bike for dusty group rides. More detail: what do pre-filter plugs do?
Rottweiler Performance Replacement Filter (7340)
Running the Rottweiler Performance intake? The 7340 at $47.94 is the FunnelWeb pyramid foam element made to fit it. More detail: the Rottweiler intake filter, explained.
Which setup for your riding?
| How you ride | Recommended setup |
|---|---|
| Mostly pavement, occasional gravel | Main Filter with Frame (7339) |
| Regular dirt, group rides in dust | Full Kit (7336) |
| Multi-day backcountry, desert, racing | Full Kit (7336) plus a spare element (7338) in the luggage |
| Rottweiler intake installed | Rottweiler Replacement Filter (7340), plus plugs (7337) if your setup uses them |
Orders over $80 ship free within the USA. Every option except the spare element qualifies on its own.
Does it actually hold up?
"After 4 days of riding in dry Southern California the outside was almost completely brown, while the inside was a yellow as the day it came out of the package. Great filtering." - Dirt Rider
That is the whole job in one sentence: dirt loads on the outside, spread across twice the area, and the side facing the engine stays clean.
Frequently asked questions
Does the same system fit the 790, the 890, and the Norden 901?
Yes. The three bikes share the airbox design, so all five options fit each of them. Order from the product page for your bike: KTM 790 Adventure, KTM 890 Adventure, or Husqvarna Norden 901.
Can I clean and reuse these filters?
Yes, that is the point of foam. Wash, dry, re-oil, reinstall, and one element serves for seasons. Never use No-Toil brand oil or cleaner on a FunnelWeb filter; its chemistry attacks the foam adhesive. Full walkthrough: how to clean and re-oil a foam air filter.
How often should I service it?
Dust decides, not miles. See the 890 Adventure service interval guide for a breakdown by riding type.
Get set up: KTM 890 Adventure filters · KTM 790 Adventure filters · Norden 901 filters. Free US shipping over $80.