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10 Tips For Proper Foam Air Filter Maintenance // AJAX Tech Tips

Posted By: Ajax Motorsports
Post Date: 08/31/2017


“Pay now or pay later…” – a phrase used commonly when talking about maintenance is possibly never truer than when describing dirt bikes. These machines, when properly maintained, can be the most fun one can legally have; but when poorly maintained, dirt bikes can be costly and even dangerous (mechanically speaking).


 There is a large variance as to what defines proper maintenance, which is why we’ve taken it upon ourselves to educate our consumers about the products we sell and how to take care of them. We believe that in taking care of people for the small things, they’ll come back for the bigger things – whether service or new bikes.


One sect of bike care that has a lot of different views is how to properly care and clean foam air filters. There are so many products and opinions out there, it can be hard to figure out what is best.


CUT AND DRY: Air filters must be cleaned regularly. They must be oiled thoroughly. AND they must seal correctly. At the very least if you meet these criteria, you are doing alright. But let’s dive deeper to subtopics you may not have considered.


Tip 1: Keep your air box clean. There are covers available to make it possible to power wash inside the air box or to make space to clean it out. The dirt that builds up inside the box can be a huge liability when removing and installing the filter. Reduce the risk of getting junk in the air boot by making it a habit to clean the air box too.


Tip 2: Coat the air box: We recommend WD-40 or penetrating fluid, this makes it easy to wipe out as well as leaves a film to catch dust before it gets to the filter. Think, every bit of dust that doesn’t make it to the filter means a cleaner filter…


Tip 3: INSPECT.  Depending on how careful you are and what products used with the filter effects the life of the filter. Harsh chemicals degrade the structure of the foam and rough handling can result in tears. Inspect the filter for tears and rips. Foam has a shelf life – if the foam feels really soft and doesn’t hold shape, it’s time to replace it.


Tip 4: Be gentle. Never wring the filter when cleaning or oiling. This puts too much strain on the cells of the foam.


Tip 5: Solvents. Don’t use harsh chemicals such as gasoline or contact cleaner on filters. These degrade the structure of the foam and significantly shortens the life of the foam. Use a mild solvent like the ones made by Twin Air or Maxima or a spray variety made specifically for foam filters. You can also buy mineral spirits and solvent with high flash points at auto parts stores.


Tip 6: Save Money. Get a wide mouth funnel and auto paint strainers. You can reclaim the solvent after use by straining the dirt out. This will prolong your supply of solvent but you will eventually need to replace it once it gets too dirty.


Tip 7: Rinse! Use dish soap and luke-warm water after using solvent. Rinse from the inside out. You’d be surprised what solids come out of the filter this way. This also preps the filter to receive oil the way it was designed to. Be sure to let the filter thoroughly air dry before applying oil. Do not use pressurized air to dry the filter faster.


Tip 8: Get Sticky. There are a lot of great options available for air filter oils. Be sure to use a purpose specific oil designed for air filters. Do not use engine oil – it was not designed to be sticky. If you opt to use aerosol based filter oils, be sure to let the oil warm up after spraying. It comes out freezing cold and working the filter too soon can result in cracking the foam. Use disposable gloves for hopefully obvious reasons.

Tip 8.1 - For pourable oils, most have an aluminum seal on the bottle. Puncture small holes in seal in several places to make it easy to pour without flooding the filter.


Tip 9: Grease. Regardless of the filter, use a generous coat of grease around the inner lip of the filter where it seals to the bike. This increases the quality of the seal and serves as an extra precaution to stop dirt. This is an extremely important step and is often overlooked.


Tip 10: Have multiple filters. I haven’t met anybody who loves cleaning air filters. Do yourself a favor and have at least one extra filter. Clean all your filters at the same time and have the spares oiled and ready to go in a zip-lock bag. This significantly cuts down on maintenance time and in the event you find a flaw in a filter, you won’t be forced to use it.