AMSOIL Air Filter Oil
AMSOIL Air Filter Oil (AFO) is a tacky, fast-penetrating spray-on lubricant for foam airbox filters used on dirt bikes, ATVs, UTVs, snowmobiles, and other powersports machines. It is sold in 14-ounce aerosol cans and is designed to soak into a clean, dry foam element, then stay in the foam to trap dirt, sand, dust, and water without restricting airflow to the engine.
Tacky formula that stays in the foam
Air Filter Oil uses a tacky base that adheres to foam fibers throughout the airbox, including the deeper layers that a thinner oil tends to drip out of after a few minutes of riding. The tackiness keeps the oil from migrating down to the bottom of the airbox where it cannot trap incoming dirt. The result is a uniformly oiled element that captures particles across the full surface area of the foam.
Quick penetration and uniform coverage
The aerosol delivery and the low-viscosity carrier let the oil penetrate the full thickness of a clean, dry foam filter quickly. After spraying, gently kneading the filter works the oil through the inner foam so that no dry spots remain. Dry spots are where dirt and dust make it past the element, so full saturation is what a properly oiled foam filter delivers.
Resists water and protects airflow
The tacky formula resists wash-out from water hits common to mud rides, river crossings, and rainy enduros. At the same time, the oil layer is thin enough to maintain the airflow rate the engine expects, so power and throttle response are not affected by the maintenance cycle. The tradeoff between dirt-stopping and airflow is what foam-filter design exists to balance, and a correctly oiled element is the only version of the filter that meets both goals.
How to oil a foam airbox filter
Air Filter Oil is applied to a clean, dry filter. Cleaning, drying, and oiling are a single maintenance routine that should be done together at the manufacturer's recommended interval, more often in dusty riding.
- Wash the foam element with a foam-filter cleaner per the bike or machine manufacturer's instructions, then rinse thoroughly.
- Press the element between clean towels to remove water. Allow it to air-dry until completely dry.
- Shake the can vigorously. Hold the can a few inches away from the filter and spray evenly across the outer surface.
- Gently knead the filter by hand to work the oil through the full thickness of the foam. Add more oil to any dry spots and knead again until the element is uniformly saturated.
- Install the element per the owner's manual. Clean the airbox sealing surfaces before reinstalling.
Recommended applications and service
Air Filter Oil is intended for foam airbox filters on motocross and off-road motorcycles, ATVs and UTVs, snowmobiles, and similar powersports applications. It is not designed for paper or cotton-gauze panel filters, which use different filtration chemistry. Pair the maintenance routine with the rest of the AMSOIL powersports program in the AMSOIL motorcycle oil guide and the oil filter guide, and confirm the application against the AMSOIL Vehicle Lookup Guide.
Typical product details
| Property | Value |
|---|
| Product code | AFO (AFOSC) |
| Package | 14-ounce aerosol spray can |
| Filter type | Foam airbox filters |
| Application method | Spray and knead onto clean, dry filter |
| Performance attributes | Tacky base, quick penetration, water-resistant, maintains airflow |
| Country availability | Not available in Canada |
| Warranty | AMSOIL Limited Liability Warranty |
Order AMSOIL Air Filter Oil
Air Filter Oil is sold in 14-ounce aerosol cans under the AFO product code. AMSOIL products are backed by the AMSOIL Limited Liability Warranty. Confirm the right maintenance routine for the machine through the AMSOIL Vehicle Lookup Guide and the AMSOIL motorcycle oil guide, then order AMSOIL Air Filter Oil.
Frequently asked questions
Can Air Filter Oil be used on cotton-gauze or paper filters?
No. AMSOIL Air Filter Oil is designed for foam airbox filters. Cotton-gauze panel filters (the type used on most street cars and trucks) and paper panel filters use different oils or no oil at all. Using a foam-filter oil on a cotton-gauze element will not deliver the intended airflow or filtration result and may damage the media.
How often should a foam filter be cleaned and re-oiled?
Service intervals depend on riding conditions. Dusty desert and motocross riding can call for cleaning and re-oiling after every ride. Trail riding in moderate conditions may extend the interval to several rides. The owner's manual for the bike or machine sets the baseline; visible dust on the inside of the airbox is a sign the interval has been pushed too far.
How much oil should be applied to one filter?
Spray until the foam shows uniform color and the surface is wet across the full element, then knead the oil through the foam by hand. Add more to any dry spots until the inner foam is saturated as well. There is no fixed ounce-per-filter figure because filter sizes vary; the visual and tactile saturation check is the standard.
Will the oil drip into the airbox?
A correctly oiled and re-installed foam filter holds the oil in the foam. Dripping is usually a sign of overoiling, a torn filter, or skipping the kneading step that distributes the oil through the element. After installation, wipe the airbox sealing area before fitting the airbox cover.
Is Air Filter Oil safe on aluminum airbox parts?
Yes. The formula is intended for use inside an enclosed airbox and is not aggressive toward aluminum, plastic, or rubber sealing surfaces. Standard aerosol-handling guidance applies: shake the can, spray in a ventilated area, and keep the can away from open flame.
Is Air Filter Oil available in Canada?
No. Per the AMSOIL data sheet, Air Filter Oil (AFO) is not currently available in Canada. The rest of the AMSOIL powersports lubricant lineup remains available, and the AMSOIL motorcycle oil guide covers the matching engine oil and filter program for Canadian and U.S. owners.
