Air Filters.

[michael]

My air filter has a small nick in it so needs replacing, what air filters are people using? Or are there any you wouldnt use?

Thought about going away from foam/OEM and trying cotton ie; K&N.
Its for the WR.
Any thoughts/comment welcome.

Thanks,
Michael.

[Rich]

For dirt I would continue using foam...

Easier to clean and oil regularly, with everday products...

[michael]

I already have K&N cleaner and oil for the pre runner.

[Renton]

I wouldn't be using the K&N type filters or use that oil on a foam filter in a dirt bike.

Go for a twin air filter. They're a dual layer foam filter. And get some good filter oil like belray, motorex etc. Put the oil into a heavy duty bucket (that has a lid) and dunk the filter in it, then just squeaze out any excess oil.

[michael]

Ok cotton filters seem to be unpopular.
You say twin air, preffered brand? as opposed to uni filters pro comp or other brands....

Michael.

[Munut]

I'm giving these a shot TORPEDO7 Foam Air Filter - 2 pack - Torpedo7
They look to be good quality and have been good so far. Great price for 2 filters.
As above use foam filter oil, I also grease the lip to ensure a excellent seal.
I wash mine with citra force, this is a natural product that won't degrade the foam. Mix at about 4:1 with water in a container massage your filter and get all the old filter oil out then rinse with the hose and it should look brand new.

[Renton]

+1 for putting grease on the face of the filter. I've been using those $2 cans of degreaser to clean my filters. Cleans them up really well and dosen't seem to deteriorate the foam at all.

Twin Air is my prefered brand. I suppose they must be pretty good as KTM use them as standard item.

[michael]

Well cullys stock twin air, Ill grab one when I get back to perth, thanks guys.

Michael.

[mx502]

Maxima - ProFilter Air Filters - BTO Sports buy a heap of these last a wile and come pre oiled so its easy when your feeling lazy

[benlikesbikes]

I'm giving these a shot TORPEDO7 Foam Air Filter - 2 pack - Torpedo7
They look to be good quality and have been good so far. Great price for 2 filters.
As above use foam filter oil, I also grease the lip to ensure a excellent seal.
I wash mine with citra force, this is a natural product that won't degrade the foam. Mix at about 4:1 with water in a container massage your filter and get all the old filter oil out then rinse with the hose and it should look brand new.

I'm running them too, glad someone else thinks they are alright, wash the oil out in kero (which I seem to have in my head doesn't rot the filter like petrol) then the dirt out in detergent then rinse then hang them out to dry.

I don't grease the lip of the filter, I have in the past and it just makes a messy thing messier, never had an issue with dirt getting in that way, I just rely on the oil working around the lip as it does elsewhere. can anyone convince me it's needed?


i got the torpedo 7 oil filters TORPEDO7 Oil Filter - 5 pack - Torpedo7 too ( one pack of each size) and havent' had any issues with them either, although, you only know you've had an oil filter problem when it's too late...

[Shady7/8]

I don't grease the lip of the filter, I have in the past and it just makes a messy thing messier, never had an issue with dirt getting in that way, I just rely on the oil working around the lip as it does elsewhere. can anyone convince me it's needed?

The grease acts as a sealant - a very tacky sealant. Basically without teh grease, the edge where you would grease it becomes the easiest path for air to get sucked in, it WILL lift and allow air to pass directly, unfiltered, into the system. Modern 4 stroke dirt bikes are very succeptible to dirt through the top end.
In the end... up to you whether that bit of mucky grease saves you or not.

I wouldn't risk it in any dirt bike let a lone a high strung KTM...

[Munut]

I was under the impression greasing the lip was very much being extra safe as you do already have super tacky filter oil on your filter and once installed the filter cage presses pretty hard into the lip and air box. I do it all the time to be safe but thought it was more important in very wet conditions.

Ease up on the KTM comments if you haven't noticed they make up nearly 50% of the dirt bikes out there.

[Shady7/8]

er whut?
Take a deep breath, step away from the keyboard, re-read what was posted.


Ease up on what comments - my point about the KTM is it's a race bike out of the box = high strung = be extra cautious on your servicing and maintenance and care.

[Rich]

KTM may be race ready out of the box and better than the Japs...

But modern KTMs require no extra servicing compared to the Japs...

Both my KTMs were ridden hard and did hours that would have you replacing valves on your Honda or Yamahas...

Never did anything but oil changes, filters, plugs and a valve clearance check...

[Munut]

er whut?
Ease up on what comments - my point about the KTM is it's a race bike out of the box = high strung = be extra cautious on your servicing and maintenance and care.

Bit like owning a Ferrari

[darkfibre]

Bit like owning a Ferrari

A bit like having it at the workshop for 75% of its life? I hope not.

[benlikesbikes]

The grease acts as a sealant - a very tacky sealant. Basically without teh grease, the edge where you would grease it becomes the easiest path for air to get sucked in, it WILL lift and allow air to pass directly, unfiltered, into the system. Modern 4 stroke dirt bikes are very succeptible to dirt through the top end.
In the end... up to you whether that bit of mucky grease saves you or not.

I wouldn't risk it in any dirt bike let a lone a high strung KTM...

OK I wasn't aware of the lifting of the filter letting air in, like others have said, the cage and spring press the filter on pretty well. how/when does this lifting occur?is it during overrun or backfiring?

I'm still not sure how the grease combats this any better than the filter oil.

Just trying to understand.

Thanks

Ben.

[Shady7/8]

The grease needs to be applied LIBERALLY i.e. thick. This creates a decent thick gluggy seal. The air filter oil is tacky, but not sticky.
Also as you spread the grease wide across the sealing face it presents a larger surface area of adhesion. you do get a small amount of lift as the filter is under tension from the frame, but overall the lift is barely 5%

The lifting will occur during hard acceleration... the worst time for it! As you create so much vaccuum in the carb and air tube the suction will find a weakest point, and this is the edge seal if only held down by filter oil opening it up to draw raw air through.
There are other kits out there that help to alleviate this happening, but if running a straight foam filter... use grease.

To use a practical example take 2 pieces of flat plastic and apply grease to each side and squish together - try to pull apart. Clean and do the same with filter oil (once it's set) see which comes apart easier... That's why grease wins over filter oil

I'm extra cautious as I've cut extra holes in my airbox to allow more air draw for SM racing

[I Fancy Holidays]

The grease needs to be applied LIBERALLY i.e. thick. This creates a decent thick gluggy seal. The air filter oil is tacky, but not sticky.
Also as you spread the grease wide across the sealing face it presents a larger surface area of adhesion. you do get a small amount of lift as the filter is under tension from the frame, but overall the lift is barely 5%

The lifting will occur during hard acceleration... the worst time for it! As you create so much vaccuum in the carb and air tube the suction will find a weakest point, and this is the edge seal if only held down by filter oil opening it up to draw raw air through.
There are other kits out there that help to alleviate this happening, but if running a straight foam filter... use grease.

To use a practical example take 2 pieces of flat plastic and apply grease to each side and squish together - try to pull apart. Clean and do the same with filter oil (once it's set) see which comes apart easier... That's why grease wins over filter oil

I'm extra cautious as I've cut extra holes in my airbox to allow more air draw for SM racing

87.6% of statistics are made up on the spot.

PS. grease the fucker, its not really that messy if you have basic coordination.

[96]

Just using this thread as it's alteady got a few heads that will look in here...

Filter socks.

I know they are great for white beach/lancelin type sand, which somehow lodges itself in side the filter element, as apposed to sticking to the outside like most of your black/red dust. So will be using one on those rides.

How do the socks go in dust though? Would you bother, or just trust the freshly oiled filter to do it's job?