Required Tools: You’ll need a T-handle to remove your seat (probably a 10mm), a clean wash bucket, air filter cleaning solution (solvent or gasoline can be used, but expect them to reduce the life of your filter), dish soap, water, rubber gloves, foam filter oil, contact cleaner and paper towels.
To get to your air filter, you’ll first need to remove the two bolts that hold your seat on. Slide your seat completely off the bike to access the dirty filter. With your rubber gloves on, turn the filter wing nut that’s fastening your filter in the air box in the counterclockwise direction. Pull the filter upward and out of the air box, but take care not to knock any dirt particles down into the carburetor intake air boot.
Your air filter element will be attached to a filter cage or screen. It may be made of all plastic, or it may have a metal screen attached, depending on the make of the bike. Remove your filter from its cage and, using a paper towel and some contact cleaner, clean the cage thoroughly to prepare it for re-installation with your soon-to-be-clean filter. Inspect the filter inside and out for any tears or ripped glue seams.
There are a number of different solvents that are capable of cleaning the oil, dirt, and grime from your air filter, but we recommend using a proper filter cleaning solution to prevent damage that could be caused by more potent solvents. Pour your solution into a clean wash bucket and submerge your dirty filter. Continue washing and squeezing the filter in the solution until it appears to be free of all dirt and oil. Try to prevent twisting or wringing the filter to help maintain the integrity of the glued seams. Repeat this cleaning step in a bucket of warm, soapy water to ensure that all of the dirt has been washed out. Finally, using a garden hose, rinse water through the inside of the filter out to push any remaining particles away from the inside surface. Squeeze as much of the water out as possible, and then hang the filter to air dry. If time is a factor, a blow dryer on low heat can accelerate the process. Just don’t get the filter too hot, or damage to the foam and glue may occur.
Your clean, dry filter is now ready for some fresh filter oil. With a clean pair of rubber gloves on, drain the oil directly out of the bottle and on to the filter. Go around the entire filter surface, inside and out, until you feel you have enough oil to spread evenly throughout all of the foam.
It’s very important to spread the oil throughout the entire filter, so make sure it penetrates all the way through. If the filter is over-saturated, squeeze out the extra oil into your solution-filled wash bucket. If there is still excess oil, paper towels can be used to remove it. Simply wrap the filter in a couple paper towels, and squeeze. Again, avoid any forceful twisting or wringing. With the filter oiled and ready to go, put the cage/screen back inside the filter, making sure the factory tab on the cage lines up with the hole in the filter.
STEP 6: Clean Air Box & Reinstall Clean Filter
Before placing that clean filter back into the air box, grab a couple clean paper towels and some contact cleaner, and clean out the inside of the air box. Wipe the ring that the filter seals against, and clean the surrounding area thoroughly. Again, be very careful that no dirt gets knocked down into the air boot. With the filter back in and the cage tab lined up with the hole in the air box, tighten the wing nut, reinstall your seat, and go ride!