Wicked Webby's Airbox Mod

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Not a naysayer here...nope, nosirree. Running pods on my ZRX has been more than enough proof to me that late model bikes can surely benefit from intake mods when combined with increased fueling and exhaust mods. Without the fuel and exhaust mods, it's more than a waste of time...it can be detrimental due to excessive lean running.
What bothers me the most is your stretching the filter media "flat" for your air cleaner.

Looking at picture #11 above, I count 19 pleats. That's 38 segments for filtering.

Two pictures later, you've stretched out the pleats to fit your template, 6 segments wide.

So you've effectively reduced your filtration media by 85%.

I plan to check mine at every oil change.
Nope...not nearly often enough!

Yamaha calls for cleaning the filter every 10,000km, or 6200 miles. You have just increased your filter maintenance schedule to every 930 miles. Have fun wid dat!

Remember that half of the stock air filter is blocked by that funnel thing. I bet the side of the stock filter that faces away from the intake tubes doesn't get much use either. If the parts of the filter in the most direct airflow get clogged, then those other parts would start to come into play, but my stock air filter has never been very dirty at the recommended service interval. Mostly a couple bugs and pieces of grass stuck in the pleats that are a pain to get out (which would probably just fall off my flat filters when I turn the bike off and the suction stops).

Based on all that has been discussed, I still believe that it's reasonable to expect that these filters could be just fine with 4,000 mile cleanings. However, all this speculation is really worthless. I'm aware of the possible issues and I'll keep a close eye on things over the next 4,000 miles. If they get questionably dirty before then, I need to look for a better solution. If they look good at 4,000 miles, I'll clean them anyway and be happy.

 
Looking at picture #11 above, I count 19 pleats. That's 38 segments for filtering.
Two pictures later, you've stretched out the pleats to fit your template, 6 segments wide.

So you've effectively reduced your filtration media by 85%.

...

Yamaha calls for cleaning the filter every 10,000km, or 6200 miles. You have just increased your filter maintenance schedule to every 930 miles. Have fun wid dat!
And don't forget that I have 2 air filters of about that same size (one on each side), so about double your estimated service period. Factor into that the unused portions of the stock filter, and 4,000 miles seems reasonable.

 
Looking at picture #11 above, I count 19 pleats. That's 38 segments for filtering.
Two pictures later, you've stretched out the pleats to fit your template, 6 segments wide.

So you've effectively reduced your filtration media by 85%.

...

Yamaha calls for cleaning the filter every 10,000km, or 6200 miles. You have just increased your filter maintenance schedule to every 930 miles. Have fun wid dat!
And don't forget that I have 2 air filters of about that same size (one on each side), so about double your estimated service period. Factor into that the unused portions of the stock filter, and 4,000 miles seems reasonable.
Pickles and others,

Please remember: I have run my (this) air box setup for a year now. As has been stated, my air box / filter setup does not have as much filter element as the stock pleated filter.. Being a flat surface and all. Although, remember that the UNI and other sponge type filters also do not have a pleated surface.

When these filters get dirty, they look dirty, but still do a great job filtering air.

Last year, I started off checking my filters every 3000 miles (every oil change). I then decided to clean/re-charge them every other oil change (6K). At 6k they look somewhat dirty but not overly bad (by any means). Based on this, I have since decided to clean/recharge them every 9k.

BTW, KnN calls for a clean/re-charge every 50,000 on their pleated Motorcycle filters. I wouldn't go that long but just saying.

https://www.knfilters.com/filtercharger.htm

Also, Pickles, great points on the stock filter style and air box funnel. The stock setup and funnel only allows for half of the stock style filter element to be used. Saying that, air wants to follow the least path of resistance. Soo.... How much of the stock filter is really being utilized? Rhectorical... I know, you have already addressed this and answered it.

Blah, blah, blah..... Doesn't really matter to me.

Bottom line is this:

This is a awesome and great air box/filter setup.

Dyno proven and all.

Far Superior than anything else out there!

PERIOD.

WW

 
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Remember that half of the stock air filter is blocked by that funnel thing. I bet the side of the stock filter that faces away from the intake tubes doesn't get much use either. If the parts of the filter in the most direct airflow get clogged, then those other parts would start to come into play, but my stock air filter has never been very dirty at the recommended service interval.
I disagree somewhat. The part that is clean behind the snorkel tube still flows air, therefore contributing to reducing the restriction of the filter. The reason it isn't as dirty is because the dirt particles have a higher mass (than air) and they don't want to make the U-turn to the section of filter shielded by the tube. There is uniform vacuum suction on the engine side of the filter, so air will flow through the entire surface of the media. It will also be drawn in from the back side of the filter as the air box acts as a plenum, so that side of the filter will be at the same vacuum as the engine side.

Opening up the ends of the box as you and Webby have done will cause less restriction into the airbox. Dat's gud!! Restriction causes the pressure in the box to be lower than atmospheric. So opening it up will allow a higher air pressure on the dirt side of the filter, increasing flow through the filter to the vacuum in the intake.

So since the goal is to maximize airflow by minimizing intake restriction, we should open the airbox intake up as much as possible, but also maximize the area of the filter media in the box.

 
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Pickles and others,
Please remember: I have run my (this) air box setup for a year now. As has been stated, my air box / filter setup does not have as much filter element as the stock pleated filter.. Being a flat surface and all. Although, remember that the UNI and other sponge type filters also do not have a pleated surface.

When these filters get dirty, they look dirty, but still do a great job filtering air.

Last year, I started off checking my filters every 3000 miles (every oil change). I then decided to clean/re-charge them every other oil change (6K). At 6k they look somewhat dirty but not overly bad (by any means). Based on this, I have since decided to clean/recharge them every 9k.
Thanks for reporting your results of real world usage of this setup. I think a year of observing the performance of your filters should be enough hard evidence that this setup should hold up just fine. I hope to reproduce your results to provide another statistical data point to prove the practicality of this airbox mod. If my air filters fail spectacularly, then I will accept that this mod is pushing the limits and is not safe (and that Wicked Webby just got lucky). I would then attempt to improve the mod and try again.

I'm sure that much of the theory and speculation on air filter size and pleated vs. flattened is correct. But what really matters is the actual amount of strength/restriction/filtration/clogging/etc that occurs in real life conditions. If the end result is that the filters hold up without clogging unreasonably quickly, collapsing or failing in any other way in real world usage, then it doesn't matter at all that flattening the filter decreased strength and decreased the service interval. This could be one of those situations where the stock parts were designed with excess safety margin (either intentionally, or just by convenience of manufacturing/assembly) and there's plenty that can be safely compromised for extra engine performance.

Now when will my headers be ready for me to pick up so I can put my bike back together and start testing these air filters? I could be enjoying the extra power instead of debating airflow theory on the internet :D

 
Not a naysayer here...nope, nosirree. Running pods on my ZRX has been more than enough proof to me that late model bikes can surely benefit from intake mods when combined with increased fueling and exhaust mods. Without the fuel and exhaust mods, it's more than a waste of time...it can be detrimental due to excessive lean running.
Very good point. If you don't at least have a power commander (or some other means of adjusting fuel delivery) with plans to get the fueling custom tuned on a dyno, then this mod is probably worthless.

On the other hand, if you're already putting time/effort/money into aftermarket exhaust and any type of fuel tuning, this is a cheap mod that may be worth doing before tuning the fuel delivery just to make sure you get every last bit of reasonably accessible performance out of the bike. For me, this mod will be complementing my holeshot headers, remus hexacone slip-ons and Motty AFR Tuner :yahoo: I can't wait to try it :dribble:

 
Not a naysayer here...nope, nosirree. Running pods on my ZRX has been more than enough proof to me that late model bikes can surely benefit from intake mods when combined with increased fueling and exhaust mods. Without the fuel and exhaust mods, it's more than a waste of time...it can be detrimental due to excessive lean running.
Very good point. If you don't at least have a power commander (or some other means of adjusting fuel delivery) with plans to get the fueling custom tuned on a dyno, then this mod is probably worthless.

On the other hand, if you're already putting time/effort/money into aftermarket exhaust and any type of fuel tuning, this is a cheap mod that may be worth doing before tuning the fuel delivery just to make sure you get every last bit of reasonably accessible performance out of the bike. For me, this mod will be complementing my holeshot headers, remus hexacone slip-ons and Motty AFR Tuner :yahoo: I can't wait to try it :dribble:

Your gonna love it!!

Only advice I have for you is to really consider adding those extra mid spaced riv-nuts. It isn't gonna hurt anything, and well worth eliminating the question of whether or not it might leak. I didn't think mine would of had an air leak either. You got the time right now vs finding out later (when the season is on).

Just my thoughts,

WW

 
Just a old FYI:

When I did hare scrambles back in the '70's, we would use grease to seal all the filter sealing surfaces to prevent dirt & water from entering any crack or warped area. Plus we would grease the entire inside of the airbox to catch any stray junk and it would give us a tell-tale indicator of a leak.

 
Pickles & WW you both have done this mod. I saw some dimensional information in WW's original post concerning this air box mod but not in Pickles unless I missed it. I decided to check out the K&N website under the flat panel filter selector section. This allows you to input different filter sizes and the selector picks the nearest match. I came up with a K&N YA-1602-U which is a pleated flat panel filter that has a outside dimension of 5.438" X 4.313" with a .688 height or thickness. This is a replacement filter for the Yamaha XV 1700 Warrior. I haven't taken any airbox measurments but this filter may be adaptable as is on the left side and possibly the right side mounting them outside. Any thoughts. :D

 
Pickles & WW you both have done this mod. I saw some dimensional information in WW's original post concerning this air box mod but not in Pickles unless I missed it. I decided to check out the K&N website under the flat panel filter selector section. This allows you to input different filter sizes and the selector picks the nearest match. I came up with a K&N YA-1602-U which is a pleated flat panel filter that has a outside dimension of 5.438" X 4.313" with a .688 height or thickness. This is a replacement filter for the Yamaha XV 1700 Warrior. I haven't taken any airbox measurments but this filter may be adaptable as is on the left side and possibly the right side mounting them outside. Any thoughts. :D
I didn't measure the size of my filters. They are based solely on the of the left-side opening to the air box (the opening when the left-side cover is removed; not the small oval opening). My left-side filter is exactly the same size as Webby's, and the right-side filter is probably quite similar.

The toughest part about using a pleated filter wouldn't be finding the right size, but fabricating the mounting hardware. The right-side filter (the square one) might actually be able to be mounted just like I'm mounting the flat filter now (but with longer screws to go through the thickness of the pleated filter's frame), but the left-side would be quite tricky. The flat filter is conveniently pinched in place by what's left of the stock air box cover after it is trimmed. Around more than 1/2 of that opening on the left side, there is no portion of a wall or lip that could be used to mount an air filter against:

airbox_trimmed.jpg


Necessity is the mother of invention. If it turns out to be unnecessary to have pleated filters (which is quite probable based on Webby's experience), then I'm not going to go through the effort of finding a way to mount them.

 
Pickles & WW you both have done this mod. I saw some dimensional information in WW's original post concerning this air box mod but not in Pickles unless I missed it. I decided to check out the K&N website under the flat panel filter selector section. This allows you to input different filter sizes and the selector picks the nearest match. I came up with a K&N YA-1602-U which is a pleated flat panel filter that has a outside dimension of 5.438" X 4.313" with a .688 height or thickness. This is a replacement filter for the Yamaha XV 1700 Warrior. I haven't taken any airbox measurments but this filter may be adaptable as is on the left side and possibly the right side mounting them outside. Any thoughts. :D
Jstewart,

I hear you knocking. Last year, I did the same thing on KnN's site. My original

plan was to use the flat pleated. The mounting of them posed a problem. In

fact, my first custom cut filter was a flat pleated cut to match the clutch side.

What was needed was some type of leak proof (along the pleats on the edges)

attaching plate. I then went back to the drawing board, spoke to a lot of fellow

wrench turning motorheads, professional mechanics and private racers. Then

came up with my filters.

WW

 
What if...

instead of fitting the filter inside the box you made some kind of an adapter plate and mounted the rectangular, pleated filter on the outside of the box?

Would there be enough space to do something like that and still get all the covers back on? It looks like the left side would be the more difficult. Basically, you would be adding the thickness of the pleated filter, plus the thickness of the adapter plate (plus something to sandwich it in place) to the outside dimension of the box.

 
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Had to stop by the Yamaha dealer to see about having the ignition sw recall done and checked on the K&N filter for the Warrior referenced above. Forget that since they want $109.00 each for them. Know I can get them cheaper on the net but still pricey. The stock Yamaha Warrior filter is $16.00. Back to square one (WW & Pickles far simpler solution) for now.

 
What if...
instead of fitting the filter inside the box you made some kind of an adapter plate and mounted the rectangular, pleated filter on the outside of the box?

Would there be enough space to do something like that and still get all the covers back on? It looks like the left side would be the more difficult. Basically, you would be adding the thickness of the pleated filter, plus the thickness of the adapter plate (plus something to sandwich it in place) to the outside dimension of the box.
I don't think there is enough room to mount a pleated filter on the outside of the right-side of the airbox. All the ABS and linked braking junk is right there. If there is enough room, there's no way you could remove the filter for cleaning without removing the airbox. Actually; you couldn't even get the airbox back on the bike with anything mounted to the outside. It's already a pretty tight fit through the frame. I think any solution for the right side has to be mounted on the inside of the airbox.

 
WW I remember you pointing out how cheap a replacement air box was in you're original thread concerning the airbox modification.

You were right and I ordered one Saturday from my dealer. The box was only $33.00. The right side filter is the tricky part because

of all the ABS plumbing in the way. I wanted to have the complete box out of the bike to experiment with. I also did some additional

research and found the high pricing on the K&N filter for the warrior was for 2 filters, one of which has a fancy molded in lip. The filter

I want to experiment with is the lower filter of the pair which has a much lower cost. The lower Warrior filter from Yamaha is also a

possability for the right side and looks to definately be mountable from the inside of the airbox. This filter is only about $16.00 but is

smaller than the K&N so I want to order and play around with the K&N first.

 
WW I remember you pointing out how cheap a replacement air box was in you're original thread concerning the airbox modification. You were right and I ordered one Saturday from my dealer. The box was only $33.00. The right side filter is the tricky part because

of all the ABS plumbing in the way. I wanted to have the complete box out of the bike to experiment with. I also did some additional

research and found the high pricing on the K&N filter for the warrior was for 2 filters, one of which has a fancy molded in lip. The filter

I want to experiment with is the lower filter of the pair which has a much lower cost. The lower Warrior filter from Yamaha is also a

possability for the right side and looks to definately be mountable from the inside of the airbox. This filter is only about $16.00 but is

smaller than the K&N so I want to order and play around with the K&N first.
Let us know how you do.

WW

 
Only advice I have for you is to really consider adding those extra mid spaced riv-nuts. It isn't gonna hurt anything, and well worth eliminating the question of whether or not it might leak. I didn't think mine would of had an air leak either. You got the time right now vs finding out later (when the season is on).
Just my thoughts,

WW
You're right. I have plenty of time now while waiting for my headers and my bike is already partially disassembled. It only took about a half hour to get the air box off again. I'm glad I did too, because I discovered that silicone adhesive doesn't glue those nuts to the back of the air box well enough. I'm trying again with epoxy. I'll update the original post with my adjustments later.

 
Only advice I have for you is to really consider adding those extra mid spaced riv-nuts. It isn't gonna hurt anything, and well worth eliminating the question of whether or not it might leak. I didn't think mine would of had an air leak either. You got the time right now vs finding out later (when the season is on).
Just my thoughts,

WW
You're right. I have plenty of time now while waiting for my headers and my bike is already partially disassembled. It only took about a half hour to get the air box off again. I'm glad I did too, because I discovered that silicone adhesive doesn't glue those nuts to the back of the air box well enough. I'm trying again with epoxy. I'll update the original post with my adjustments later.
Pickles,

Glad to hear it.

Keep us posted.

WW

 
Per Wicked Webby's recommendation, I added 4 more screws to the right-side filter to prevent leakage past the seal:

rhs_filter_mounted_update.jpg


I also discovered that the silicone adhesive doesn't hold those nuts in place too strongly. I popped one off the air box while applying pressure and trying to get a screw started. I tried epoxy now, but am having doubts about it. I think the final solution will be some good duct tape framing the hole on the right side of the air box. The nuts only need to be held in place enough so that they won't pop out. The spikes driven into the plastic will take care of holding them from rotating as you tighten the screws.

 

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