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K&N Air filter Installation and Performance Analysis

Posted: Sun Dec 11, 2011 12:20 am
by maddiedog
To determine once and for all if the K&N air filter is worth the upgrade, I went ahead and ordered one. The cost was only $33.80, including shipping, from Amazon.com.

As usual with Amazon, the package came in 2 days.
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Some propaganda:
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I opened up the box and took out the filter:
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The air filter is designed to last the lifetime of the vehicle, or is guaranteed to last 1 million miles, whichever comes first.


The air filter on the PCX is located on the back-left of the scooter:
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Looking in closer, the filter's behind this box:
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Remove the 8 screws holding the cover in place, and the cover and filter will fall out into your hand:
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Lift the filter out.

Here's what the stock filter looks like next to the K&N filter. As you can see, the K&N filter has larger ribs and more surface area for air to pass through, theoretically increasing airflow, and therefore performance and/or efficiency.
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The stock air filter's filter component's dimensions are 5.25" wide by 3.25" tall, or just over 17 square inches.
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The K&N filter provides more cross-sectional area than the stock air filter -- about 5.5" wide by 3.5" tall, or just over 19 square inches.
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To reinstall, place the K&N filter where the stock filter was previously, and screw it back in place.
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Before the installation, I came up with a quick test set to see how the air filter would perform. I decided to do 3 runs on flat ground, and 3 runs uphill, all at full throttle to see how quickly the scooter would attain top speed. Then, I installed the K&N filter and repeated, doing 3 more runs on flat ground and 3 more runs uphill.

The test platform, my PCX:
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Video of the speedometer was recorded using my Droid II, then edited post-run on my computer to determine times. Droid mounted in place:
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In addition, it has been mentioned before that, for the ECU to remap, the battery would have to be unplugged. To ensure fairness, I unplugged the battery for 5 minutes before the initial tests with the stock filter. Then, I ran the 6 tests with the stock filter, changed out the filter for the K&N filter, unplugged the battery for 5 minutes again, then ran the 6 tests with the K&N filter... Battery unplugged:
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0-60 times on flat ground with the stock air filter
Run 1: 14.92 seconds
Run 2: 13.97 seconds
Run 3: 14.19 seconds
Average: 14.36 seconds

0-60 times on flat ground with the K&N air filter
Run 1: 14.72 seconds
Run 2: 13.40 seconds
Run 3: 14.15 seconds
Average: 14.09 seconds


0-50 times uphill with the stock air filter
Run 1: 25.88 seconds
Run 2: 28.62 seconds
Run 3: 26.54 seconds
Average: 27.01 seconds

0-50 times uphill with the K&N air filter
Run 1: 28.55 seconds
Run 2: 24.95 seconds
Run 3: 29.12 seconds
Average: 27.54 seconds


On flat ground, the scooter was, on average, 0.25 seconds faster with the K&N air filter.

Uphill, the scooter was, on average, 0.53 seconds slower with the K&N air filter.


And here's the video proof of all that, in case you care to view it:



Both test results had large P-values (0.6024 and 0.7503) due to the large range between the run times. It is clear that results were inconsistent due to varying wind, a lack of rider skill, or inconsistencies in the fuel injection system. To draw results conclusively, with statistical significance, several hundred runs would be required. That said though, it is apparent that there is not a profound difference.


Given the maintenance schedule calls for replacement every 10000 miles, and the K&N filter costs about 4 times as much as a stock filter, the K&N filter is an economical option if you plan on putting over 50000 miles on your scooter.


I have begun tracking my gas mileage again to discern if the increased airflow will improve efficiency. I'll update in another 1000 miles or so with my new gas mileage. :)

Re: K&N Air filter Installation and Performance Analysis

Posted: Thu Dec 22, 2011 1:53 pm
by trigg123
nice post mate well done for taking the time to do it
and merry xmas to you all

Re: K&N Air filter Installation and Performance Analysis

Posted: Thu Dec 22, 2011 3:29 pm
by nasnikos-Greece
Well done Dave,
we need your final conclusion!

Re: K&N Air filter Installation and Performance Analysis

Posted: Thu Dec 22, 2011 3:44 pm
by nasnikos-Greece
Dave, check this out...
It's another filter made in Greece..
Seem to be wider than K&N.

Image

Here's the site..
http://www.e-dnafilters.com/Product.asp?ID=1483

Re: K&N Air filter Installation and Performance Analysis

Posted: Thu Dec 22, 2011 9:14 pm
by maddiedog
Wow, looks to add a whole lot more airflow. Now that, I might expect to make a difference... My testing showed that there isn't really any noticable improvement with the k&n...

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 1:17 am
by nasnikos-Greece
I think that the only improvement with these filters is in our pocket!
Every common filter costs 12-15 euro. ECONOMY! IMF is hunting us!!!
Hehehe

K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 9:46 am
by spongebobnopants
Glad to see folks still driving this late into the year. I went to start mine the other day and the battery was dead. I wanted to run some some stabil through it. I have it plugged in now and she ran rough for 10 seconds, But then smoothed out. I'll just be starting it every 2 weeks or so and let run for a few min.

Anyhow, I did a similar test with similar results to maddie. When I sell the scooter, I'll put the barely used eom back in and sell the K&N for $25. Wash.

I have played around with different variators after that, so I have no idea about better mileage, but I get ~100-110mpg with lighter rollers and the K&N. I miss riding as my cage is yielding about ~15mpg on winter blend.

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 10:26 am
by Fiah
spongebobnopants wrote:Glad to see folks still driving this late into the year. I went to start mine the other day and the battery was dead. I wanted to run some some stabil through it. I have it plugged in now and she ran rough for 10 seconds, But then smoothed out. I'll just be starting it every 2 weeks or so and let run for a few min.

Anyhow, I did a similar test with similar results to maddie. When I sell the scooter, I'll put the barely used eom back in and sell the K&N for $25. Wash.

I have played around with different variators after that, so I have no idea about better mileage, but I get ~100-110mpg with lighter rollers and the K&N. I miss riding as my cage is yielding about ~15mpg on winter blend.
Dear lord, why? Just to make sure that you ruin it?

Either properly winterize it (change oil, brim the tank and add stabilizer, remove battery), or take it for a proper spin every once in a while (at the very least 10 miles, preferably more). Starting it and letting it idle is just about the worst thing you can do in the long term. The wear of an unnecessary cold start + idle is bad enough, but what you are also doing is ruining the oil by starting the engine regularly without bringing the oil to operating temp. That allows water and unburned gas to build up, which really doesn't help lubrication. And you'll be draining the battery as well.

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 11:50 am
by Woolley
thats exactly what the dealer told me to do over winter...
Although i bought that trickle charger anyway from recommendations off here.

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 11:55 am
by EddieC
Spongebob - I didnt know you were planning on selling the PCX?

K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 5:12 pm
by spongebobnopants
Not planning on it, but I'm sure I will at some point. Anyhow, its not insured during the winter, so I can't drive it. Now that I ran some stabil through it, I guess I'll just leave it on the charger and not start it.

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 5:37 pm
by EddieC
ah got it. I'm not planning on getting rid of mine any time soon... I bought it thinking I would have it for a year or two, but I'm loving the little 125. If anything, I would get another bike before replacing my PCX

Re: K&N Air filter Installation and Performance Analysis

Posted: Fri Dec 23, 2011 6:35 pm
by maddiedog
Fiah - Most dealers recommend people doing so to make sure their batteries don't die over the winter. It's silly and a bit bad, but it won't destroy your engine. Unless you plan on owning the scooter 20 years, it won't matter.

That said, as long as you keep your battery on a charger and put some fuel stabilizer in it, you can store it for a really long time without doing anything else. Just be sure to do an oil change in the spring before any rides.

Spongebobnopants, do you take it off insurance to save money? It would seem like being a repeat customer would reap more of a discount than removing insurance for a fourth of the year...

Re: K&N Air filter Installation and Performance Analysis

Posted: Sat Dec 24, 2011 3:28 am
by Fiah
maddiedog wrote:Fiah - Most dealers recommend people doing so to make sure their batteries don't die over the winter.
Well I don't know about the PCX, but many motorcycles actually discharge their batteries at idle.

K&N Air filter Installation and Performance Analysis

Posted: Sat Dec 24, 2011 8:17 am
by spongebobnopants
I forget what the insurance calls it exactly, but it's covered for theft and everything, just helps lower the overall rate since they know it won't get used during dec.-feb.

As for the charger, it's a smart one and doesn't constantly trickle.

Re: K&N Air filter Installation and Performance Analysis

Posted: Sun Dec 25, 2011 5:39 am
by nasnikos-Greece
Hey, great offtopic guys..!

Re: K&N Air filter Installation and Performance Analysis

Posted: Tue Dec 27, 2011 12:15 am
by EddieC
nasnikos-Greece wrote:Hey, great offtopic guys..!
Hey, great input!! :lol:

Re: K&N Air filter Installation and Performance Analysis

Posted: Mon Jan 02, 2012 5:57 am
by PT63
I've had a K&N filter installed for about six weeks and have not noticed any improvement at all. :(

Re: K&N Air filter Installation and Performance Analysis

Posted: Tue Jan 03, 2012 4:00 pm
by maddiedog
At least you'll never have to buy a paper filter. ;)

Re: K&N Air filter Installation and Performance Analysis

Posted: Wed Jan 04, 2012 3:59 am
by EddieC
just bought a k&n myself from amazon... mainly because I hate shopping, and will only have to buy it once =]

I dont expect to see a performance increase but im curious to see if itll make any difference on "the big hill" on my way home... Usually top out at 45 for a half mile stretch of road. Will report back but I'm not expecting much of a difference if any at all