Wicked Webby Air Box Mod Warning

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UselessPickles

Making Grand Canyon replicas from air boxes...
Joined
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If you don't know what the "Wicked Webby" air box mod is, read this: https://www.fjrforum.com/forum/index.php?showtopic=114873

So here's my custom air filters after about 4,000 miles:

dirty_filters_outside.jpg


That's the outside facing sides of the filters. Pretty dirty, but it was to be expected that I'd have to clean them fairly often (I was going with every oil change). Now let's check out the inside facing sides...

dirty_filters_inside.jpg


OH CRAP! That doesn't look good. In case you miss it, there's a chunk of the aluminum wire mesh missing from one of the filters. My guess is that the creases in the wire mesh were weakened when I flattened the pleats, and the engine sucked it off.

I took my air box off and searched everywhere in the air box, the intake tubes and throttle bodies hoping to find it lodged somewhere. It was nowhere to be found. One of my butterfly valves has a light scrape on it, and one of the intake valves for the same cylinder had some black gunk on it (looked at it through the fuel injection port while shining a flashlight in through the throttle body). The rest of my intake valves were spotless (sorry; no pics). My guess is that the wire mesh got trapped by the valve until it melted.

So how bad could this be? My engine has been running just as good as always with no unusual sounds, vibrations or loss of power. I assume that any damage has already been done by now. I'll be ordering a new air box and only modify it partially so that a stock-style air filter can still be used to prevent my engine from eating any more air filters.

Any suggestions on how to assess the possible damage? How likely is it that I got away with insignificant damage?

 
Useless~

I think you probably dodged the bullet on this one, simply because the missing mesh is aluminum, not steel.

It apparently didn't lodge anywhere in the intake system, from your careful inspection and the fact that all functions as well as it always has. I'm guessing that the very light gauge aluminum wire in the mesh simply "vaporized" in the heat of the combustion chamber!

Shouldn't be any lasting damage... Thank God!

Don

 
I'm new to the forum, but not new to wrenching. I say that if you were going to have any problems from this, you would already know. I say you got lucky this time. Is that clump still on the intake valve? If so, I would recomend pulling the throttle bodies and intake boots and trying to get it off the valve. It will eventually come off, and then where's it going? If it's melted into a "clump" then it's probably pretty hard stuff...

 
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Is that clump still on the intake valve? If so, I would recomend pulling the throttle bodies and intake boots and trying to get it off the valve. I will eventually come off, and then where's it going? If it's melted into a "clump" then it's probably pretty hard stuff...
Yup; it's still there. It wasn't really a clump. It just looked like a fairly thin coating of lumpy black gunk. I'll be able to get to it when I replace the air box soon. Any suggestions on how to go about cleaning it off the valve and how to get the debris out of the intake port? There's not much room to work there. It would be so much easier to clean if I could just take the valve out, but my inexperience with working on engines would probably cause more damage while taking the top of the engine apart to get at the valves.

 
I think you probably dodged the bullet on this one, simply because the missing mesh is aluminum, not steel....

I'm guessing that the very light gauge aluminum wire in the mesh simply "vaporized" in the heat of the combustion chamber!

Shouldn't be any lasting damage... Thank God!

Don


I say that if you were going to have any problems from this, you would already know. I say you got lucky this time.
I like the sounds of that! I can sleep a bit easier now. I'll sleep even easier once I get the new air box installed. Speaking of which, I better order the parts now.

 
Pickles,

Thanks for the PM regarding this. That sux! Obviously something

was bad with the KnN you started with. Never seen a KnN filter

do such a thing. How that metal screen could have a cut out missing

From it (like you posted) is down right suspect... Maybe sabatoged??

My KnN filters, with 23k on them, have never suffered

or resembled that fate. My Brother's 06 (with his KnN Flattened filter) has also

never shown any signs like that. Glad you caught it.

Though it is very much a flawed KnK filter verses a problem with the mod (as your thread

title implies).

I would let KnN know about what happened to that filter.

Maybe they will have some insight on this for you(For example;

How have you been Cleaning them.. How much oil and what

kind have you been using... How'd that steel screen get damaged? Ect..)

BOTTOM LINE.... Flawed filter ,NOT a flawed setup.

WW

 
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Pickles

I'm inclined to agree that if you are going to have problems, you'd know it by now. What you can do is pull the spark plugs and do a compression test. Any valve damage or cylinder/ring damage would show up.

+1 on the new air box. The reason your filters are so dirty is you actually decreased the filter media surface area by un-pleating them. I count maybe 6 pleats worth of filter media.

dirty_filters_outside.jpg


Count the pleats on a stock filter, it should be around 25 or 30.

When you go back the original construction just open up the far end of the box the same internal diameter of the stock air filter. Of course, take the snorkel off and the internal baffle tube. You should have plenty of breathing then. The added benefit will be an easily replaceable, robust air filter.

It's just a slight set back. :glare:

Brodie

 
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When you go back the original construction just open up the far end of the box the same internal diameter of the stock air filter. Of course, take the snorkel off and the internal baffle tube. You should have plenty of breathing then. The added benefit will be an easily replaceable, robust air filter.
It's just a slight set back. :glare:

Brodie
That's the plan. I won't be able to do that in time for my scheduled dyno tuning session this Saturday, but I do have a second set of clean custom air filters that I've put in for now until I get the parts. Based on Wicked Webby's response, I think it should be safe to go ahead with the dyno tuning session with my new CLEAN filters. I bet the dirtiness of the filter had something to do with it ripping apart.

After I get the new air box, I'll do another quick dyno session to find out how much difference there is between the partially modded air box and the full-blown Wicked Webby mod.

 
The missing screen section is downright weird and mysterious. But I think the main evidence you show against the flattening of the K&N filters is the amount of dirt seen on the back side of the filter after only 4k miles. This shows that the filter is not adequately filtering the air. If you look at a paper auto that has been in service for 10 times that the engine side of the filter is generally pristine looking even if the outter side is caked with dirt.

 
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Pickles
I'm inclined to agree that if you are going to have problems, you'd know it by now. What you can do is pull the spark plugs and do a compression test. Any valve damage or cylinder/ring damage would show up.

Brodie
Agreed. Also, when you pull the plugs, be very careful not to bang them around when you take them out. Inspect them very closely with a magnifying glass for small globules of aluminum stuck on the electrode. Back in my wrenching days, we busted a customer for holing the piston (said it was our fault, but we suspected he had put in too hot a plug) on his 125 but we didn't find any AL in the spark plug. Every other bike we'd ever seen that had holed the piston showed AL on the plugs. I would expect to find something similar when the K&N mesh went through the combustion process.

You were lucky. Sometimes shit self destructs, sometimes it just flys thru. We had a 35,000 HP, 10,000RPM compressor that apparently ate the suction screen. Screen was there after start up, gone a week later when we had to take it apart for something un-related. Had to have gone thru the machine but we never saw it. On another occation, similar thing happened and we wrecked the compressor in seconds.

 
" Any suggestions on how to go about cleaning it off the valve and how to get the debris out of the intake port? There's not much room to work there. "

Chemicals, small wire brush, maybe a bore brush for a shotgun or such. Vaccuum it out as good as you can. Oh, And make sure valve is closed when doing this. You can duct tape a piece of fuel line to the vaccuum hose to get down in the port good.

Good luck!

 
When you go back the original construction just open up the far end of the box the same internal diameter of the stock air filter. Of course, take the snorkel off and the internal baffle tube. You should have plenty of breathing then. The added benefit will be an easily replaceable, robust air filter.
It's just a slight set back. :glare:

Brodie
That's the plan. I won't be able to do that in time for my scheduled dyno tuning session this Saturday, but I do have a second set of clean custom air filters that I've put in for now until I get the parts. Based on Wicked Webby's response, I think it should be safe to go ahead with the dyno tuning session with my new CLEAN filters. I bet the dirtiness of the filter had something to do with it ripping apart.

After I get the new air box, I'll do another quick dyno session to find out how much difference there is between the partially modded air box and the full-blown Wicked Webby mod.

Never liked the idea of the "furnace filter" mod. Just not enough downstream support with all the potential vacuum when/if the panels became partially blocked/dirty. I did the partial by just using a 1 1/4" hole saw on the right side of the airbox for the upper and lower radius of the I.D. , then trim the middle nubs with a dremel. Cut back the stock intake snorkel tube that fits into the stock filter to about 1/2" length and kept the external slot snorkel off.

Did a dyno yesterday and gained 4HP at peak and 5 pounds torque right in the middle of the RPM range. Lost power or torque nowhere. Cheapest (cost $0.00) and fastest (30 minute mod) power gain I have ever seen. Don't believe it? Call Richard at Santa Cruz Cycle Imports. He ran the dyno and will attest to the fact. (831) 479-3667

I just dont see the need to go all the way and cut out giant holes in the airbox. I mean at 9500 redline and 100% VE, the feej can only pump 230 CFM anyway. Two oval holes the size of the ID of the OEM filter is more than enough area to flow up to that level.

 
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<snip> Did a dyno yesterday and gained 4HP at peak and 5 pounds torque right in the middle of the RPM range. Lost power or torque nowhere. Cheapest (cost $0.00) and fastest (30 minute mod) power gain I have ever seen. Don't believe it? Call Richard at Santa Cruz Cycle Imports. He ran the dyno and will attest to the fact. (831) 479-3667<snip>

*minor hijack*

Karl -- can you post the dyno curve from your run? Inquiring minds want to know...Thanks

--G

 
Hmmm... I seen to remember some discussion on the reasons for pleating in air filters. Seems you have just proven all of the rational for more surface area. :rolleyes:

 
Karl,
Do you have any pic's of your method? Sorry, i don't want to hijack this thread just interested.

Dave

This is nothing more than the old "Cdogs" mod seen here. https://www.fjrforum.com/forum/lofiversion/.../t105719-0.html

All I did differently is use a holesaw to make nice clean cuts on the upper and lower radii. Then use a Dremel to trim the small V-shaped nubs that are left on the left and right sides of the oval where the holesaw didnt cut. Trim the snorkel tube on the left, clean up the cuts with sandpaper or file and you're done with the fabrication part.

I checked my TBS after and it was still good to go, but YMMV. Also, I have a PC3 and Richard did have to make a 3-4% adjust down low in the RPM range on the partial throttle columns as I was leaned out a bit below 4K. The 100% throttle was unchanged.

 
<snip> Did a dyno yesterday and gained 4HP at peak and 5 pounds torque right in the middle of the RPM range. Lost power or torque nowhere. Cheapest (cost $0.00) and fastest (30 minute mod) power gain I have ever seen. Don't believe it? Call Richard at Santa Cruz Cycle Imports. He ran the dyno and will attest to the fact. (831) 479-3667<snip>
*minor hijack*

Karl -- can you post the dyno curve from your run? Inquiring minds want to know...Thanks

--G

Yes, I'll try to get over the hill to SC tomorrow and get Richard to print it out. Then I'll scan and post here. I didnt really expect too much from it, really just wanted to verify that the Tuninglink he did back in April was still OK after the mod.

 
I would let KnN know about what happened to that filter. Maybe they will have some insight on this for you(For example;

How have you been Cleaning them.. How much oil and what

kind have you been using... How'd that steel screen get damaged? Ect..)

BOTTOM LINE.... Flawed filter ,NOT a flawed setup.
So your suggestion is...

Brrrring! Brrrrring!

Joe, the K&N Customer Service Rep: "Hello, this is Joe at K&N. How can I help you today?"

Useless Pickles: "Yeah, hey, Joe. I took one of your perfectly good filters, cut it up, flattened it and stuck on my bike's airbox (also cut up and modded) for use in a way never intended by either you or my bike's maker. For some strange reason, the screen on my now cut up and flattened filter broke and I think my bike sucked a piece into an intake &/or cylinder. I think your filter's flawed."

Joe, the K&N Customer Service Rep: :blink: "Right. You did what..?" :huh:

Maybe he should push for a warranty replacement while he's at it..?? :blink:

 
I would let KnN know about what happened to that filter. Maybe they will have some insight on this for you(For example;

How have you been Cleaning them.. How much oil and what

kind have you been using... How'd that steel screen get damaged? Ect..)

BOTTOM LINE.... Flawed filter ,NOT a flawed setup.
So your suggestion is...

Brrrring! Brrrrring!

Joe, the K&N Customer Service Rep: "Hello, this is Joe at K&N. How can I help you today?"

Useless Pickles: "Yeah, hey, Joe. I took one of your perfectly good filters, cut it up, flattened it and stuck on my bike's airbox (also cut up and modded) for use in a way never intended by either you or my bike's maker. For some strange reason, the screen on my now cut up and flattened filter broke and I think my bike sucked a piece into an intake &/or cylinder. I think your filter's flawed."

Joe, the K&N Customer Service Rep: :blink: "Right. You did what..?" :huh:

Maybe he should push for a warranty replacement while he's at it..?? :blink:

:rofl: :rofl: :rofl:

 
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