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Has anyone installed a DNA filter?


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Well don't listen to this lot then:-p
Honda SS50, Kawasaki Z200, Honda 400/4, Yamaha TDM900, Yamaha XT660Z Tenere, KTM 990 Adventure, BMW R1200GS, Mr Stevens, and my favourite of all: Yamaha MT-09 Tracer...a bit like FJ-09 only properly named :¬P
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Lots of opinions out there, and some dubious test data on flow and dirt captured.
 
Here's my take:
 
There are a few types of filter media.
Depth and paper holes. That's pretty much all of them. (Unless you want to put a charged media unit into your motorcycle.. not very practical.)
 
Both can be oiled to improve the ability of the media to stick and collect dirt from the air flow.
But paper holes are limited in how much dirt they can hold/trap in that as each hole is plugged up with dirt, it closes the hole. That limits flow as the paper filter becomes dirty over time and with use.
 
Depth filters, both dry using static charge to attract and hold dirt, or oil to wet and make the media sticky to dirt.
 
These are excellent! They tend to trap larger dirt out in the outer layers of the filter media, and the smaller stuff deeper into the media. Also the oil can "wet" the dirt and debris, causing it to actually ENLARGE the filter area, and trap more dirt and debris as it passes by.
 
It's very common to take a K&N, or DNA type filter, or even oiled foam filters and "knock" dirt and debris from them by lightly tapping the filter against the side of a trash can inside for example. This dirt being knocked loose is usually wet with oil from the gauze/foam filter media, and most filters of this type are over-oiled anyway. (This can cause problems on MAF sensors, especially hot wire ones, or Karmann mirror/hertz wave designs where the disrupted air flow is measured out in a hertz signal that the ECU can calculate air mass/volume from. AUDI's are very problematic with K&N filters causing problems with the MAF being covered with oil residue, and then the ECU throws up the CEL.)
 
Our bikes have a MAP sensor, AIT and TPS that's built into the e-throttle, so the engine can calculate the fuel needs, and then trims it by feedback from the O2 sensor. The base fuel map is "built" into the ECU and can be modified for more power, or less pollution, and changes in timing advance etc. all play on power output and "feel" of the engine to the rider.
 
But the filter media seems to flow plenty of air stock, as there is little to be gained by just a filter swap from what I've read here and on the FZ09 boards when I had the FZ09.
 
Some air flow gains might be found by carving up the air box lid, removing the snorkle and such, but the reality is, the volume of the air box appears to be designed by Yamaha from the start to allow this engine to reach it's potential if other things are done right. (Exhaust and ECU tune/parameters for example.)
 
One you guys who likes math can do the calculation for this engine at various RPM rates, including at the REV limiter, where the max amount of air would be drawn through the filter media, and then see if there is anything to be gained in reality.
 
If the stock filter is a depth media, lightly oiled, which it appears to be, it's going to flow pretty good. Sure, a LARGER filter area, or media with more open gauze that depends on more oil to work correctly might flow more at lower pressure changes. (And that's key too, as air flows from high to low pressure ALWAYS. And the lower the restriction, the more power in theory the engine can make at any given RPM, so even at 2000 RPM, it's going to make more power, if there is less restriction to the filter to the pressure change. You gain this power as a reduction in pumping losses. It takes less energy to get the same amount of air into the chamber, so you see more power at the wheel/crank.)
 
My guess is the FZ09/FJ09 airbox and stock filter flow plenty of air at the range this engine is designed for from Yamaha. So, minimal changes in pumping losses from a change in filter media, or slight increase in filter area due to deeper pleats, or more pleats is going to offer changes that are hard to quantify.
 
So. With all that, I'm waiting for PiperCross to come out with an oiled foam flat panel filter for our bikes. I've used them on other bikes, and I like them best. It's two or more densities of oiled foam backed with a metal screen to keep it's shape, and the flow v/s dirt catching ability of this style of filter is excellent. (Way better than oiled cotten gauze for example.) They seriously work better and flow better as they become more dirty. The dirt becomes wet, and expands the surface area of the filter media.
 
To clean it, you just take the unit out, gently knock the dirty debris out, and put it back in and ride more.
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  • 4 weeks later...
So, I have to add that I've done more research on this, and found the following.
 
The stock engine, at about 850cc even if it runs up to 10,000 RPM, with a factor of 0.8, common for non forced induction gas engines... Is about 120cfm of air. (At 10,000 RPM.) At lower RPM, where most of our riding is done, it's less, much less.
 
So, if the DNA flows even 200cfm of air, and the CP3 engine can't use more than about 120cfm... It's a moot point. (Thus why I think most tuners have found that the stock filter works fine, it flows more than the engine can "use" at any given RPM that the bike is typically going to see.)
 
I used a simple calculator on the net that is easy to search and find if anyone wants to try it out. I used this on many turbo engines. Add a turbo to the FJ09 CP3 engine, and you might need as much as 300 cfm at 10k RPM.
 
But, on our non-forced induction engines, even if they were really effective designs, the amount of air needed is about what the stock filter flows already. The DNA, and any other filter would just be less restriction, but the higher flow rate would not be used by this engine unless you either raise the RPM range, really make it efficient or force air into the intake side.
 
Gains on the exhaust side are pretty minimal too, but can be had by improving flow, often at the expense of being much louder. And might lose some low end torque that is dependent on low speed exhaust flow and how well the exhaust can remove it from the chamber v/s at higher speed. (Most high flow systems lose low end torque at the expense of high RPM power, but not all.)
 
SO? In the end, I'm just going to run the stock filters. They are cheap, and work great it appears.
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i had akrapovic with oem filter last year. in straight or even a highway with declivity my topspeed was 224-225 km.
 
now i have akrapovic 2017 model with dna... road with acclivity (tested twice) i reached 227-228 km/h easily and very quickly. i had also strong wind and isotta 53,5 cm screen in tallest position.
 
the ecu is not flashed yet.

MODS: custom remapped 133 wheel power by T.R.E. / K&P WORKSHOP,  WOOLICH RACING + race tools package, reprofiled cams,  ported cylinder head,  higher compression, bored throttle bodies, ape cam tensioner,  OHLINS FGK237 cartridge & YA 535,  GPR V4, SKF Fork seals,  BREMBO RCS 19 Corta Rossa with SC pads, HEALTECH shift light PRO, AKRAPOVIC racing carbon exhaust, slipper clutch + Barnett clutch springs, JT Sprockets + JVMX 525 black 112 links chain, oil temp gauge drain plug, air filter DNA + Modded airbox, PIRELLI ROSSO CORSA II, YAMAHA LED plus blinkers, antitheft alarm scorpio 900i + perimeter sensor + kill engine module, CELLULAR INTERPHONE led slim fog lights with yamaha oem mounting bracket, YAMAHA heated grips and more....

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Thank god the FJ'09 has a nice airbox setup compared to my FZ'07... But I wanna mention 1 thing, that is... the engines ability to get its volume of air is also dependant on its efficiency to get its volume of air...if the airbox set up is done right one should not need to upgrade the air filter to my knowledge...
 
For example the FZ'07 got like 4 mile long intake tubes and using a higher flow air filter netted decent gains due to the engines ability to get its volume of air more efficiently with less resistance compared to OEM....I know the engine is not taking in anymore air than it needs but it's getting it's volume of air with far less resistance and better efficiency...
 
I run 2 huge High Vacuum Braze ovens that run at -30 Inches of Mercury... We lose vacuum (pumping) efficiency when the plumbing gets dirty inside so every like 3 months we gotta send a chimney sweeper snake brush thru the plumbing to knock out all the crud and voila we got our vacuum efficiency back...
2012 wr250f - C-class 30+ age group
2015 fz-07- Hordpower Edition-80whp
2015 fj-09- Graves Exhaust w/Woolich tune by 2WDW @120whp
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I totally agree on pumping losses, and low restriction flow rates.
 
But I'm just posting up that if the max cfm of this engine is 120 cfm at 10k rpm, it's going to use much less across the "normal" range of engine speeds, say 4k while you are in town. You would notice very little change going from a filter that is rated to flow nearly 150 cfm of air. (And going to one that's rated to nearly 200 cfm of air is going to be over kill even more.)
 
Put a super charger or turbo on this bike, and pull through the stock air box? It would need the DNA filter. (And slightly more, about 300 cfm by my calculations.)
 
Has anyone done some cutting of the airbox to see if there are any gains to be had by removing, modifying or adding to the snorkle and air box? I think there was something posted up about cutting the box, but not any gains to be had? Sound is important, and engine that sounds powerful is fun, and some intake snort is a fun thing to have. (just like a louder exhaust is fun, but sometimes does not any power in reality.)
 
We know the filter flows more air than the engine will need. (Stock.)
So, does the air box noise design restrict airflow? I don't have a flow bench or it would be easy to see. (Test it with a filter, and without.) Then do some mods to the air box, and see what happens, shorten the snorkle by a few inches each time.. remove it completely, remove the inner oil traps.. add more intake surface area to the front part of the air box on the "Dirty" side of the filter... Drill some holes LOL
 
Try some heat shields? Cut out hot air from the engine/radiator. Any cool air intake mods easy to do? Rain or water issues?
 
would adding a filter to the PCV vent help to remove oil vapor into the air box/engine? (You want the air flow, but not the oil as it dilutes the air fuel mix... And a simple foam or oiled foam filter plugged into that "vent" would trap most of that oil, and let it drip back into the engine case v/s being burned off by your engine, or becoming deposits on the intake/exhaust valves...
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I did see a thread on the FZ-09 forum awhile back about on of the vendors by the name of Marthy I believe who cut the front top of the airbox out...gonna go track it down, curiosity. ....
2012 wr250f - C-class 30+ age group
2015 fz-07- Hordpower Edition-80whp
2015 fj-09- Graves Exhaust w/Woolich tune by 2WDW @120whp
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So I found the FZ-09 airbox mod, well 3 mods...all were not worth cutting up airbox unless your chasing every iota of power... the stock airbox and filter are well thought out...
 
@piotrek I have been looking at that same turbo kit for a few years, the air filter for that set up is actually located on the turbo itself...need to see if the FZ and the FJ share same airbox part #, otherwise I see no reasons why it shouldn't fit...the FJ would lose the center stand and would have to cut the center stand stop bracket off, if using the PCV map, I'm 99% the ECU has to has to be flashed back to OEM if flashed, and I'm 50/50 on rather or not the TCS needs to be on or off...
 
This same kit and an FZ-10(with an FZ-10 specific airbox) made same peak  HP btw ?
2012 wr250f - C-class 30+ age group
2015 fz-07- Hordpower Edition-80whp
2015 fj-09- Graves Exhaust w/Woolich tune by 2WDW @120whp
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Warranty? ? Me No Habla English...
 
low psi barely 7psi and race gas is how they accomplish 200hp ?
And I don't quite believe 207hp, they did a little dyno trickery  by letting rear wheel move forward on the roller drum, the other videos show hardly no rear wheel moving forward on the roller drum...
 
 
Edit : both the FZ and FJ share same airbox and airfilter... 
2012 wr250f - C-class 30+ age group
2015 fz-07- Hordpower Edition-80whp
2015 fj-09- Graves Exhaust w/Woolich tune by 2WDW @120whp
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