View Full Version : Cleaning your air filter

03-20-2005, 06:27 PM
How often do you do it? What do you use?

03-20-2005, 08:14 PM
For the foam filters on dirtbikes, i wring em out a few times with gasoline. Then i use gear oil or (if i have it) this belray air filter oil product whose name escapes me. Its the best, its very tacky when it dries a little and everything sticks to it. Its the only airfilter product belray makes. I do this before every ride religeously, trying to stretch my topends.

The paper filter in my bandit, i take it out and hit with the air hose about as often as i change the oil. If it looks bad, i replace it. I generally dump the oil every 1.5-2.5k. That big bandit can really toast the oil pretty quick, especially during the summer.

03-21-2005, 08:49 AM
My bike has a foam filter. I try to clean it every time I change my oil(every 2 months) If you have a foam filter, it's basically free to clean it. I wouldn't spend the money to replace a foam filter until it looks terrible, stains and such that can't be cleaned. I do however use a detergent to clean mine, not gasoline. I would think gas would break foam down over time, but I don't know.

03-23-2005, 07:18 AM
Could you clean a foam filter with kerosene like you do with lawm mower filters?

03-23-2005, 08:05 AM
Could you clean a foam filter with kerosene like you do with lawm mower filters?

It is the same material, but I didn't know that you could use kerosene. Is that what the owners manual said? I would be careful using such a harsh chemical on the delicate foam. But if that is what the manual calls for, then I'm sure more qualified people than me have thought it through.

04-01-2005, 09:48 AM
the one in mine is about 20 years old and has almost deteriated, imo dont need em

04-01-2005, 06:41 PM
The manual for the EX500 says to use a high flashpoint solvent. Whatever the hell that is.

04-01-2005, 10:19 PM
Lol, gasoline is a high flash point solvent. So is kerosine, but its lower on the scale.

04-01-2005, 10:21 PM
y0 ronnieboy, i'd recommend you keep an air filter in your bike and keep it clean. Its more important to small engines than even an oil change.

04-01-2005, 10:47 PM
Gas and kerosene are low-flash-point solvents. Gas is a very-low-flash-point solvent.

A high flash point solvent is one which has a flash point above 140'F. Gas has a flash point of around -40F. Kerosene is around 110F. Diesel is 120-150F. It changes from fuel to fuel. I think most halogenated solvents (carb/engine/brake cleaners) have high flash points. There are also a number of silicon (I think) based solvents that are non-flammable...

04-01-2005, 10:51 PM
Yeah, you're right, after a few beers i read that in reverse.

Acetone is another.

I guess the bottom line is, no smoking in the pits, lol.

04-01-2005, 11:45 PM
Acetone is another what? No playing with volatile organic compounds while drunk! I still don't know what the right thing to use is; since I don't want to dissolve a rubber filter. So far it's been soap and water . . . !

04-02-2005, 01:10 AM
Acetone is a low flashpoint solvent, or i think it is. I'm no chemist.

Ok, so i looked this up in 2 shop manuals. I've been doing this a long time, but ya figure old dogs can learn new tricks.

My yz shop manual actually recommends kerosine, but gives no procedure, but then that manual sucks. My kdx shop manual says use a high flashpoint solvent:
quote from page 2-15, Fuel System, KDX200 Motorcycle Service Manual:

Clean the element in a bath of high flashpoint solvent using a soft bristle brush. Squeeze it dry in a clean towel. Do not wring the element or blow it dry; the element can be damaged.

After cleaning, saturate the element with a high-quality-foam-air-filter-oil, squeeze out the excess, then wrap it in a clean rag and squeeze it as dry as possible. Be carefull not to damage the sponge filter.

If you have a foam looking filter, you are probably well served to use kerosine and gear oil. I do the same thing on my lawnmower and weedeater. Make sure you get all the gas/kerosine/whatever out by crushing it into a ball, but don't wring it like a napkin...that'll tear it. There's no need to wait, unless you want to let it dry. When i'm in a hurry i just hit it with gear oil a couple times crushing it several times and immediately slapping it back in. The first time the oil hits it you get rid of all the gas. If you use some kind of fancy filter oil, i would let it dry all the way before you apply. I know what gear oil is, but i don't know what the other stuff might be...so i'm happier with gear oil unless i'm racing in the dry summer...which means major dust.

An old trick is to put some oil into the airbox under the filter. If the oil looks dusty the next time, it means the filter is shot...or you did a shoddy job on the filter.

Its the oil that traps the dust btw, not the foam. The foam is designed to trap the oil.

04-02-2005, 01:17 AM
Whew, i need another beer after that.

11-09-2007, 08:45 PM
Don't use Acetone!!!

I just found out the hard way. Acetone will disolve the foam element.