Is their any benefit to K&N style high velocity filters on an SP2 RC? From what I understand, that low RPM surge is a RICH surge. In fact, from what I've been told, the RC is conservatively rich through much of it's powerband. I'm keeping a tight reign on spending now, so a power commander is out of the question, but air filters might be a go.

John

I wouldn't do it. From all the tests that have been done on aftermarket filters and the 51, the stock filters flow more than enough air. The k&n's can actually hurt performance more often than not. If you absolutely have to have them then go for it. If I were you I would save alittle longer for the power commander, it is every bit worth the $249 you'll pay for it.

I have read the same thing.

http://www.rc51.org/airfilt.htm

Have to agree with the above posts... save your $$ for a power commander.

Thank You, doesn't hurt to ask!

john

guys which power commander ?2 or 3?..

PCIII get the USB version for ease. I believe that is all they sell now.

http://www.solomotoparts.com/product.php?productid=18297&cat=323&page=1

Get a 3usb

Maps:

http://www.rc51.org/PC3maps.htm

Lead your my pal buddy but I just have to say.


MightyMax....unless your running sato's or moriwaki's thos maps above are useless. But if you are running those cans I heard they are badass maps and I can attest to that cause my buddy lead is running them on his bike and that thing moves!!!

Hi j. Thanks for the compliments.

Check the first one listed for stock parts and a good tune. My tune came from the same person. He is well known in the RC51 world. Make sure to check your year. Try different ones as you will never know what might work best for your bike. Ask jgos. I think he uses a Yoshi tune? for D & D pipes. I know even a tune for a stock bike should make drivability better, especially off idle, and it will feed the motor more timing and fuel throughout the RPM band.

Hi j. Thanks for the compliments.

Check the first one listed for stock parts and a good tune. My tune came from the same person. He is well known in the RC51 world. Make sure to check your year. Try different ones as you will never know what might work best for your bike. Ask jgos. I think he uses a Yoshi tune? for D & D pipes. I know even a tune for a stock bike should make drivability better, especially off idle, and it will feed the motor more timing and fuel throughout the RPM band.

I couldn't agree more. PcIII was the 1st mod I did and with a tune for a stock bike it ran alot better. I am using the Yoshi map for my d&d's and it runs great. No popping anywhere so I know the fueling is right on. Only issue with the 3usb is that unfortunately it doesn't adjust timing only the fuel trim. Now the 3r will adjust both but I don't think you can buy the 3r anymore unless you find one used. Dynojet is supposed to be coming out with an add on to the 3usb that will allow you to adjust timing. But anyways I highly recommend a pcIII. Its a great investment and is definately worth the money.

Whats up bro what you got goin on this weekend for the holidays?

Hey.

Nothing much. Going to eat with the family and hang out at my cousins farm and watch the game. You?

Check this out:

http://us.f13.yahoofs.com/bc/43ead772m53f056d6/bc/RC+51/100_1035[1].jpg?BC_YFLJBXfKxXJ.5

=)

Got my moms for lunch and my dads for dinner. I'm off on Friday but the wife isn't so I'm probably just gonna tool around the house all weekend. Might take the race car out on Sunday though !!!

That link don't work

The link was a picture of gloves. I bought some. I am trying to get my gear lined up.

LMK if you take the car out. That would be fun.

I'm usin Slip on Scorpion race cans...tks guys helpin me..i will let the RC51 member in S'pore know...

I have a set of K&N's and they basically paid for themselves, if anything the mod is well worth it for that reason. Why keep buying air filters if you can just buy one set that last the entire life of your bike. I've been seeing many K&N's going for dirt cheap on Ebay.

Just a thought, can't say I've noticed a huge gain in performance, but I bought them to save money. I've since put them on my truck and my car as well.

I also have a Scott's permanent oil filter which I think helped save money in the long run. It's well worth the investment in my opinion.

A power commander is definitely a great mod though, I got lucky and the RC I bought already had one on it. But, like everyone else has said, if you want performance gains get the PC. But, I can't honestly say that the K&N's didn't save me any money. Basically all if ever have to buy now is new oil, the rest is covered.

:D:D:D

The PCIIIUSB is a modular system now, so you can attach the timing module, quick shifter, and who knows what else in the future.
They even have a USB hub or switch that everything connects to.

Unless you know what you're doing, I wouldn't bother with the timing adjustment on the PCIIIr or PCIIIUSB timing module.
That feature was added at the request of race teams and is not really needed for the street.

Misadjusting timing on today's engines will at best lose power, and at worst destroy an engine. Too far either way with cause the engine to ping and/or overheat.

I just ordered a k and n filter for my sp1 I wish I would have read this forum first. I would have just bought a stock set and saved $40. I have a 2001 and the stock filters can't be cleaned because they have some kind of adhesive on them that collects the dust. after 2001 my manual says to just clean the stock ones with compresed air. so sorry mud if you have a 02 or newer you didn't save any $

Ahhh...didn't know that, but mine where free so no harm no foul.

Thanks for the info though.

Gotta jump in on this one. K&N are worth stepping up to, but there's a big catch. When the filter is cleaned and re-oiled chances are very good that a DIFFERENT concentration of oil (more or less, depending on the person doing the applying) will end up on the filter. Consequently, any previous set-up or adjustments made to the engine or PC will be altered because of a different rate of air flow due to the different "thickness" of oil on the filter. While the argument can be made that the same thing will happen to any filter as dust/dirt begin to accumulate, I'll opt for the long-term benefit of a re-usable, high flow filter. AS for mapping the PC, all you're doing is taking an educated guess based on someone else's findings, using their bike. (Kinda like using a reloading manual, if you're into hunting/shooting. It's a great place to start, but fine tuning the load for your gun/application is still crucial). Yes, using the MAP is better than nothing, but it's still far from the best practice. Save your pennies and put your bike on a dyno from a reputable shop. It's worth the dough and the guess work is gone because it's set specifically for your bike rather than for some "average."

the OEM filters were bench tested by a guy named Brian something in 2000 and they will flow enough to run a big block chevy, after markets are a worthless mod

the OEM filters were bench tested by a guy named Brian something in 2000 and they will flow enough to run a big block chevy, after markets are a worthless mod

"Worthless Mod." Funny, it seems most of the guys I run on the track with have either opted for K&N or BMC filters along with their other "worthless mods." Hmmm...

Aftermarket Airfilters

Testing of aftermarket airfilters on the RC51 has yielded poor results. Typically there are no real world benefits to aftermarket filters for the RC51 as small hp gains can be obtained on topend, but only with a severe trade off for mid-range hp. Truth be told every single Honda sportbike in the last 10 years has had losses in power at some point in the rev range or even throughout it from the addition of K&N , EMGO, BMC filters etc... The only real exception being the Airbox Plus kit developed for the 900RR from Factory Pro tuning which does increase hp throughout the rev range on the 900RR, but in my experience requires some pretty extensive jetting to get it right.


Interesting info #1: Flow testing on the stock filters performed by Brian Sheridan of Sheridan Racing Design proved to us that the OEM filters are more than capable of flowing more air than the engine can use


Interesting info #2: Dyno Testing on the BMC filters showed a definite decrease in topend horsepower with only a very slight gain in the mid-range. dyno charts from testing on 02/23/02

Note: when testing new high flow filters it is imperative to allow them to be broke-in properly by getting some miles on the bike at normal riding speeds. The oil applied from the factory can be initially too thick & can cause flow problems which can mis-lead dyno results in either direction. You may initially get good dyno results, but when the oil dissipates & the flow increases your dyno results may worsen or vice versa. Simply put with the extra oil in the filter you might get a good or bad initial dyno run, but after the oil is thinned out the dyno results may change (& usually do) just depends on the bikes flow characteristics

Additional common dyno testing discrepancies are discussed here dyno tuning basics



Back in the old days all the bikes benefited from slapping some individual pod filters on & adding some larger fuel jets... Things have changed greatly in the last decade whereas it's not uncommon for today’s custom jet kits to use smaller main jets with slimmer needles etc... to gain more horsepower & a more linear power delivery instead of just following the old cliché of bigger is better.

Since originally posting this page I have received hundreds of further inquiries about testing methods involving ram-air & how do I know the aftermarket filters don't work etc... Well there are more ways than just dyno testing to get results. Utilizing an Air/Fuel meter while riding in real world conditions will reveal alot of what your bike is actually doing, but even then not everything may be as it seems, sometimes a rich condition will be reported when the reason is that too much air inside the airbox is causing turbulence & stalling the airflow etc...

Some airfilters do work on certain bikes & some don't affect performance at all, but most aren't worth a damn for the overall performance advantage. The OEM filters are tuned to a specific resonance inside the airbox & once you go altering that you get various results. You might get better top end, but poor low end or vice-versa or you might get better performance with a bad stumble that lasts only for only a 200 rpm range or you may simply get a dip in power at some point. The combimation of results is almost infinite.

The main thing to remember is that on streetbikes you need drivability. If you were to put a graduated scale on your throttle housing & make a mark on your throttle grip you would find that you rarely exceed 10% throttle while riding around, yup no crap, 10%! Even when aggressively leaving stoplights & such you really don't open up the throttle all that much. So you need to have your bike as responsive as it can be at low throttle positions & in the mid-range of the bike where you ride the most. Way too much emphasis is put on peak hp when in fact you rarely ride around at redline with a wide open throttle... It's all about better mid-range performance & that is coincidently where the high flow filters usually hurt performance.

Honda's are definitely more applicable to this issue than the other manufacturers. It would appear that Honda spends more R&D time than any of the other manufacturers to insure that the intake system on their bikes is finely matched to the flow characteristics of the motor. The airbox is perfectly tuned to accept x amount of air thru the filters & deliver it to the carbs or throttle bodies in a metered volume & every thing works perfectly in sync in the state of tune they must be in to pass EPA Emissions testing. Typically an alteration of the filter leads to too much turbulent air entering the airbox & usually ends up either leaning out the motor or stalling the airflow altogether.

What would be more beneficial for creating more horsepower would be a larger airbox, which would make a larger amount of air "available" for the motor to use as opposed to a greater volume of air that the engine would be "forced" to use if you went with hi flow filters or filterless. What you don't want to end up doing is putting more air into the airbox than the engine can mix with the fuel. If that happens then you have screwed up your air/fuel ratio & you will lose power.

I'm not going to outright say that there is nothing to be gained from aftermarket filters, but I will say that most top-notch tuners will sway you a different direction especially if you are riding a streetbike as opposed to a racebike. Citing drivability issues as the number one concern.

Another point routinely thrown in my face is that the aftermarket filters are "re-usuable" Which simply put means that not only are you spending $80-$100 for a filter, but you also now have to purchase an additional cleaning kit so that you can wash, dry & oil your expensive filter, but in less time that it takes you to just wash the re-usable filter I can remove my old OEM filter, throw it away, install a new one & be off riding... If you are one of those people that are going to argue the cost savings of aftermarket vs OEM filters then you are into the wrong sport as nothing about a sportbike is cheap, not the cost of the bikes, insurance or maintenance period & you should be prepared to pay a few bucks every 4000-8000 miles for a filter.

In the end one thing is for certain if you are going to use aftermarket filters & get any appreciable gains from them it's going to require a Powercommader, alot of dyno time & probably some creative airbox mods too, maybe even to the point of fabricating custom bellmouths to get it dialed in correctly & you must also consider that in some cases there are no gains to be had & in many a loss of performance or drivability can Occur!

BTW because someone always brings up the fact that they use K&N filters in their car or truck & they do work under those conditions I must add that I too use K&N filters in my vehicles & they do show definite increases in power & throttle response, but cars are differerent from current bikes in that they have a closed loop Fi system that can compensate for the air flow variance whereas bikes use an open loop Fi system that cannot automatically compensate. Adding supporting evidence to my theories of airbox turbulence you will be interested to know that K&N has developed many different types of turbulence diffuser inserts for many different makes of cars & trucks that lessen intake turbulence when using their filters to increase performance. So far nobody has developed a way to even test for turbulence on motorcycle induction systems let alone cure it...

Does anyone have or know where I can find a PC3U tune for a 05 with Jardine slip ons and K&N filters?
I would love to try something other then this tune I bought the bike with.
The tune I have now I believe my buddy tweaked on his own, it runs fine, but I just want to try something else.

Thanks Guys.

Have you tried Power Commander's web site?
They have a lot different maps.

Yes I have looked on their site and they do not have a map for me; at least I did not see one.

They have them for 2000 and 2001, but not a 2005.

Yes I have looked on their site and they do not have a map for me; at least I did not see one.

They have them for 2000 and 2001, but not a 2005.

Did you also look for an '02-'06? They're the same bike.

Sorry I looked as well, and no Jardine anything.

@Mrgrn filter topic:
I only can agree to it.

@ Mrgrn Thema Filter:
Dem kann ich nur zustimmen.

Sure did, there is nothing for 2002 through 2006.
But there is for a 01/02 SP1.
I assume the SP1 map will not work, that much is different?

Reorganisation the original air box with big volumes.
Umbau der original Airbox mit grösserem Volumen. (http://www.rc51forums.com/forums/showthread.php?t=405&page=3)