Air box modification question

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FJROHIO

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I recently installed a K&N filter and noticed that the air box has a bit of a strange design in my opinion. I had about 3500 miles on my stock filter and noticed that only half was getting dirty.

Did anyone else ever see the air horn inside the air box. We all seem to be using only half our air filters, unless that is, air will enter the box and voluntarily do a 180 degree u-turn before heading through the filter element.

Is this some scheme to get twice the mileage out of air filters. ie, once half gets dirty flip the thing around?

Anybody ever cut the thing off? any negative side effects? it just seems terribly ineffective to me from a performance standpoint asking the air to twist and turn and in effect slow down when entering the engine.

Any thoughts?

 
Joose, on the Euro board, does a lot of development work for his on-line store, "Bikejohnny". He was doign some work on the airbox last year and IIRC he stated he got no appreciable increase so it wouldn't be worth it for him to produce anything. YMMV, but I'd hope you have access to a dynomometer to actually test the results.

 
Don't really care about the power gain. My pipes, power commander and K&N make me happy in that department.

I was more concerned about the effectiveness of the air filter. I know, I know the stock filter will likely filter better than the K&N, but damn that air horn just doesn't seem right.

No dyno here to test results, but my assomometer likes the extra power from the few performance mods I've done.

 
Methinks your ears like the sound and are transmitting their joy to your brain. @ 125 rwhp in OEM trim, you can feel the whopping 3 hp gain?

I understand because my Holeshots sure sound sweet, but I don't think my "hind-o-meter" can really detect all that biga jump in power. And if you'll go here you can find the tests Bounce did when he changed to his D&Ds, including sound tests and dyno charts.

 
Methinks you should read my post again, b-u-t s-l-o-w-e-r- this time.

Pipes may add only 3, I'll go with that, and that ALONE may not be noticable. I don't disagree with that.

How much, however, do you think my pipes, a PCIII (M409-002 map NOT the zero map), and filter would add as I posted? 10 maybe 12? Would you give me 10 on that? Do I hear at least 10!?

I think anyone's ass would notice a 8% spike in power to the ground on a 600# bike.

You disagree?

From Mark Johnson's site as you referenced:

Jim Fortner's '04 w/OEM cans, air filter, PC3=N/A or zero map (blue): 119.9 hp, 85.3 lb/ft

Mine w/D&D cans, OEM air filter, PC3=zero map, O² disconnected (red): 129.5 hp, 90.8 lb/ft

Tuned: My '03 (as above) after the dyno tune and PC3 mapping update: 131.24 hp, 91.36 lb/ft

You see, from stock by adding pipes and the PCIII -WITH ONLY THE ZERO MAP- added 9.6 horsepower to the ground before tuning. Add a filter and the 002 map and I'M SURE we'd be over 10 in gains.

Yup, my assomometer is calibrated correctly. 8-10% increase, you bet, I can feel DAT!

 
There is generally quite a bit of work done on induction systems to make sure that all cylinders flow evenly. This extends into the air box on short induction systems like the FJR and most bikes. That extension may (or may not...???) be there for a reason. Something to think about before considering cutting it off or something. Wouldn't be uncommon or unbelieveable for the system to flow a little more on the flow bench due to removing the baffle but the engine would actually make less power due to the loss in air flow distribution.

From everything I have seen the K&N filters flow LESS than stock paper elements. If you are looking for performance go with a clean stock paper element. The K&N's do not filter as well, either, so that argument doesn't fly.

About the only thing about the K&N that seems to justify it is the fact that it is reuseable....but....for the price you can buy a new paper filter every year forever and have more flow.

K&N makes a nice product and they specialize in custom aircleaners for many applications that have no other alternative but their simple replacement filter elements rarely if ever do anything for performance or filtering plugging them into production air boxes. Many years ago the modification to a K&N filter involved eliminating the production air box and such so there were performance gains seen...not just because of the oil wetted gauze filter media but because of the overall system design change. Not so true today with the well developed induction systems. K&N elements look cool and have a lot of curb appeal as they promise a lot and it is easy to change....but the results just don't bear the product out. I have done a number of engine dyno tests on automotive engines and the K&N elements never outperformed the OEM paper elements and were often worse for power in the production air boxes.

There is a lot of misconception about the air cleaner getting "dirty" and what really constitutes "dirty". If most people see a smudge of dark on the filter they think it is "used up". The filter will likely flow 95 to 100% of it's original capacity even after it is started to get covered with dirt and actually starting to cake in spots. It is surprising how much dirt an air filter can accomodate and still flow fine. The filtration capability actually IMPROVES as the filter gets dirty so if you are concerned with engine life due to contamination of the inlet air then always run a dirty filter for best filtration. Just because one spot of the filter gets dirty does not mean that the rest of the filter is not "working". The dirt and particulates in the air have some inertia and will deposit themselves on the part of the filter that they are carried to due to the flow patterns inside the dirty part of the air box. The filter can get very dirty in one spot and still will flow fine. The filter will still flow fine in the "dirty" area until it reaches the point that the dust and dirt actually cakes to the point of bridging the pleats...then the other part of the filter will have to handle all the flow and the restriction will start to increase.

Most HP gains quoted for air cleaners and induction system changes are grossly over stated from what I have seen on cars and bikes. They are just not there unless the system was a grossly restrictive system from 25 years ago.....

 
Pipes may add only 3, I'll go with that, and that ALONE may not be noticable. I don't disagree with that.
How much, however, do you think my pipes, a PCIII (M409-002 map NOT the zero map), and filter would add as I posted? 10 maybe 12? Would you give me 10 on that? Do I hear at least 10!?
I think you are living in the world of wishful thinking. ;)

I would be willing to bet that your combo added at the MOST 4hp, and I doubt it added that much. But then without dyno results it all mental masturbation anyways.

And before you go getting your panties in a bunch - I have the exact same combo you have. Only I am NOT fooling myselft that there was any huge power gain.

For your homework assignment, go to the Dynojet website and find the section where they tell you that the PCIII really doesn't increase max horsepower, but does increase hp at partial throttle settings.

And it was the Dynojet folks that told me K&N air filters really have no benefit in regards to horsepower based on their extensive testing.

So, all that is left is the Holeshots. Maybe they add a few ponies, but I have not seen any objective results, just Dale Walker's claims. With cats installed, call me a skeptic.

 
I have seen the results of the Dyno readings between the Holeshots, stock and Staintunes. With the PCIII and K&N filter and stock filter. There is about 4 hp gains with the holeshots and not really noticeable with the Staintunes. Now I am about to add the header and the PC map for Dale's system. I am making an educated guess here from other results on different bikes but I am thinking only about 8-10 hp'swith the whole thing, PC included, from 123 estimated stock to 130 ish at the rear wheel you might notice a difference where the bike is tuned, say in the midrange but probably not very noticeable if you use the seat of my pants issue. JMHO

just out of curiosity, how much do the cats weigh? I know the drop in weight of the Holeshots is almost half of the stock cans. Plus if some of us would loose say 25 lbs we could gain another 3 hps. That would save food money on the diet and $1000 for a full system.

 
Jestal-

First, very nice write up. You clearly have some wisdom to offer in this area. I agree 100% that stock paper elements filter the air better. In fact I said that on my second post of this thread. Call me old school or whatever, but I like K&N and have had good luck with them. Of course with the number of miles I put on my bike each year, It would be 20 years before the rings and valve seats would be "tired out" from the incremental dust and dirt entry. I bought the K&N partly for performance gain, and partly cost. I plan to keep the FJR for 20 years or so and even a stock paper filter every year at $15 (guess?) that's $300 or so. I'll do the K&N for $65 once and done.

I also agree with how dirty filters can get before they are restricted. I plan to let my K&N get very dirty and clean it maybe ever 25,000 miles at best. (Another reason why I liked it, because that represents about 7 years of riding before I have to pull the box cover off again.)

As far as the purpose of the air horn in the box, I'm sure the designers and engineers DID put it there for a reason. No doubt in my mind. I'm in the automotive field, and engineers many times will add something like that. Not for performance gains mind you, but maybe to clean up emissions or some other reason. I'm sure there will be a side effect if one were to remove it, but I didn't know how great the positive effects would be over the negative.

Hense the reason for this thread in the first place... I was wondering if anyone removed it and what the effects were. Hell, maybe somebody out there removed it for a slight gain in power and noticed no ill side effects? That's why I asked. (of course any results will have to be dyno tested and certified b NASA before posting any opinions or else others will shoot your post to hell...) Of course, predictably, nobody even attempts to answer my question, but rather adds their $.02 and picks apart every word each person writes in an effort to find someplace where you weren't exactly clear or attempted to make a point without written proof from a group of NASA engineers who operated the test equipment monitoring that modification. GEEEZ Everybody has to be right on this board.

Skooter-

Two quick points. According to the DYNO RESULTS from Johnson's page pasted below he did see exactly a 9.6 horsepower increase (to the ground) from a stock bike with a zero map > to his bike with pipes and a PCIII also with a zero map before tuning.

Again, I would guess that adding the more aggressive 002 map would only increase that number bringing me to my guestimate of a 10 HP increase. There's your dyno results...

From Mark Johnson's site as you referenced:

Jim Fortner's '04 w/OEM cans, air filter, PC3=N/A or zero map (blue): 119.9 hp, 85.3 lb/ft

Mine w/D&D cans, OEM air filter, PC3=zero map, O² disconnected (red): 129.5 hp, 90.8 lb/ft

Tuned: My '03 (as above) after the dyno tune and PC3 mapping update: 131.24 hp, 91.36 lb/ft

Second point: You said you have the same set up as me. and mentioned that you agree the pipes may add 3-4 horse. Even if you weren't in it for the power gain, you may simply want the sound, which is cool. That said, (and I'm not trying to be a smart ass here) if you really believe that the PCIII and K&N filter have zero performance benefit, why did YOU spend the money? Valid question, yes?

FJRVTX-

I bet when you remove those cats and have your PCIII tuned to match you will be pleasantly surprised. They probably won't save you too much in weight, but they likely represent the most restrictive part of the entire intake and exhaust system. Keep me posted, but I'll bet you will be surprised with the performance gains. Another benefit from removing the Cats that you may not have considered: Power Mist or VP race fuel.... Yup, running those fuels with converters is a big no-no, but without cats to meltdown, you will love it. Don't love it to much though, cause it's probably about 5 bucks a gallon these days. Used to run it in my motorcross bike and loved it. SORRY no DYNO results, you'll have to just take my word or try it yourself.

 
About the only thing about the K&N that seems to justify it is the fact that it is reusable....but....for the price you can buy a new paper filter every year forever
Ok, well.... this is more than just a little exaggerated. :lol:

Yamaha FJR1300 air filter: p/n 5JW-14451-00-00 - full retail price: $30.99

K&N air filter for the FJR1300: p/n YA-1301 - full retail price: $67.95

So you start saving $$$ after two airfilter changes... not too shabby. For the Endurance Riders in the community, this can add up to substantial savings over time. And, of course, one can obviously find both filters at prices lower than full retail.

As to whether they are better or worse for their intended application, personally, I'm not seeing a whole helleva lot of difference in performance either way. But piling on 30,000+ miles a year, I'm seeing a difference in maintenance costs. :D

Arguing over K&N's is similar to arguing over oil or octane use. The believers say they do the job well enough, and the non-believers demand to see dyno charts and lab tests.
shrug.gif


I just know they work for me. I use them strictly for the maintenance longevity, given the amount of miles I accumulate every year. The same K&N in the deer-strike bike also saw duty in my old Timex. This K&N has well over 60,000 miles between the two FJRs.

And well, well over 75,000 miles on the K&N filter on my Blackbird. Like I say, it appears to work for me, and this includes some rather severe service duty in very dusty Desert West conditions for the past 5 years. It certainly appears to be filtering at least "well enough" :D Below are a couple photos of the K&N air filter out of my Blackbird, taken just today (the bike is currently down for heavy maintenance and Endurance Rally preparations for the upcoming season):

~8500 miles since it's last cleaning... this is the "clean" side, facing the velocity stacks:

cleaninside.jpg


And here is the "dirty" side, facing the ram-air inlets:

dirtyKN.jpg


I've been using K&Ns for well, well over a decade of Endurance Riding competition in all of my bikes for many hundreds of thousands of miles. For me, they appear to be performing more than adequately, and I'm saving $$$ for other important items such as tires and fuel. :D I don't have charts and graphs to prove anything scientifically, but I have enough actual, real-world results using them to give me the confidence to know they are appearently working for my needs.

YMMV, etc.

 
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Yea, Warchild, I agree with you on arguing over the K&N's...LOL. I just hate it when someone expects to gain a bunch of power from installing one when the flow limitations of the whole system is rarely, if ever, the air filter element. Nothing to do with bikes, but I hate it even worse when someone cleans their K&N in one of our vehicle applications, puts too much oil on it and immediately runs into driveability issues and sets codes due to the oil fouling the MAF....and drives into the dealer and wants warranty coverage and/or blames the car. Not that I dislike K&N (I have their filters on a couple of my own specialty applications) but they do cause the automotive area some grief with their product.

In the endurance, high mileage arena there is certainly a case for the K&N for cost savings from what you show.

Based on the dirt on your filter element in the picture at 6500 miles I would say the bike is injesting pretty clean air !! and that element will go about 50K before it is really "dirty". That is a good example of what is a slightly dirty element ...just shows that it is working. I've seen people throw elements away that were cleaner than that thinking they were clogged. Seriously.

 
Skooter-    Two quick points. According to the DYNO RESULTS from Johnson's page pasted below he did see exactly a 9.6 horsepower increase (to the ground) from a stock bike with a zero map > to his bike with pipes and a PCIII also with a zero map before tuning.

    Again, I would guess that adding the more aggressive 002 map would only increase that number bringing me to my guestimate of a 10 HP increase. There's your dyno results... 

From Mark Johnson's site as you referenced:

Jim Fortner's '04 w/OEM cans, air filter, PC3=N/A or zero map (blue): 119.9 hp, 85.3 lb/ft

Mine w/D&D cans, OEM air filter, PC3=zero map, O² disconnected (red): 129.5 hp, 90.8 lb/ft

Tuned: My '03 (as above) after the dyno tune and PC3 mapping update: 131.24 hp, 91.36 lb/ft
NOT!

I have not yet reviewed Mark's page, but from info you are quoting the baseline hp figure is from a totally different FJR. Jim Fortner's 04 vs. Bounce's 03. Apples and Oranges. Was it even the same dyno? On the same day? You simply cannot make a comparison from those samples.

As for the map, did you do your homework assignment? Apparently not. So I will repeat myself - even Dynojet says it is likely there will me miniscule, if any, max horsepower improvement by switching maps with their Power Commander. :p

Again, I would guess that adding the more aggressive 002 map would only increase that number bringing me to my guestimate of a 10 HP increase. There's your dyno results..
No, nyet, nein, NOT!

When claiming *supposed* horsepower gains from the latest farkle you decided to shell out your greenbacks on, ***GUESSING*** has no place for the discerning FJR rider, and could earn you the SkooterG avatar of shame. ;)

    Second point: You said you have the same set up as me. and mentioned that you agree the pipes may add 3-4 horse. Even if you weren't in it for the power gain, you may simply want the sound, which is cool. That said, (and I'm not trying to be a smart ass here) if you really believe that the PCIII and K&N filter have zero performance benefit, why did YOU spend the money? Valid question, yes? 
For me, sound was my secondary reason for the switch, but didn't weigh much in my decision. Why did I do it? Cause I got a free PCIII out of the deal, with an adventure thrown in to boot. You see, I was the test mule for developing the Holeshot map. I rode to Dynojet's headquarters in Las Vegas so they could put my FJR on their dyno and develop the Holeshot map.

So you freaking owe me royalties!!!!!

K&N filter was for the re-useable benefit that Warchild mentions above. And I am considering just going back to the stock air filter.

 
Just to throw a different angle on all this, just how much of the stock hp can you really get on the ground? It has been my experience so far, that if I make an attempt to seriously hammer the FJR below freeway speed it is capable of breaking loose the rear tire. Right now.

I admit that I haven't tested this any kind of scientificly but at least once a truely hard launch at 55 produced some slippage and below that, well the bike can pretty much melt the tire if you really want too.

Now, is 3 or 5 or even 10 hp really gonna make much difference if you can't put it on the ground?

Yeah, I know that roll on and torque are a different matter, but just max hp? I know I'm happy with what I got. Gonna spend my money on other areas.

YMMV yaddayadda Uknow

OR didn't ya know that is why you are buying new tires every 3 to 5 k miles?

 
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Skoot, don't hold back... Let it out, man! :D ;)
Ok, so I am in a mood.......

No offense to you FJROHIO.

I am travelling and am in FJR and FJRForum denial.

Also, after 6 days in West Palm Beach, Florida hanging out on the beach and pool, sipping foo-foo drinks with little umbrellas in them, and ogling all the eye candy, I am not looking forward to returning home tomorrow. :(

 
Skoot, I hope you don't expect us to feel bad for ya.

I mean hanging out in West Palm Beach , sipping foo-foo drinks and ogling all the eye candy, damn it must be tough.

Sheesh

 
Skoot, I hope you don't expect us to feel bad for ya.I mean hanging out in West Palm Beach , sipping foo-foo drinks and ogling all the eye candy, damn it must be tough.

Sheesh
Yeah, its rough.

But ya know? Somebody's gotta take one for the team. ;)

 
Skooter-

None taken. Just so we both can see each other's side of the story.

I bought the pipes for sound mainly (didn't like the sewing machine noise). Performance was secondary. Bought them off the forum for a deal. I think $375 or so for my aluminum 2 brothers. The PCIII I didn't get for free, so yes, hats off to you, but I aint payin' no royalties! I did, however, get mine for only $100 from either this forum or the owners site I forget which. The K&N, well just because I've always been a fan like the famous Warchild.

I'll be in Orlando all next week for work.... save some sunshine for me!

 

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