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Hey boys..... I have an 02 RC51, its all stock. I want more HP. Where do I start. I'm very poor.
Trade it for a 1000cc in-line of the same year.:D

Aside from that, re-gear the bike (15/41). You will not gain any HP but the bike will "seem" faster.

I would also do the flapper and soft rev mod.
 

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I wasn't being a tool. You really want to go faster take some riding lessons. It will make you a better rider and you will get more out of your bike. I have a buddy who used to race supermoto's and he leaves my ass behind on a 600cc because he is a better rider than me. Riding lessons is one mod you can transfer to your next bike!! Bro.
 

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Unfortunately, the desire for more performance without much outlay of cash are diametrically opposed. As you no doubt already know.
At some point in time, the beast will demand a piece of your wallet.

An aftermarket exhaust with power commander plus dyno mapping can improve the bike's overall performance. Usually the improvement is due to less weight over the stock exhaust with a few extra ponies and torque added.

Improving the bike's handling is probably the best money spent.
An aftermarket shock (Ohlins, Penske, Elka, etc.) offers better suspension performance than the stock shock.
You can also install aftermarket valving in the forks as well for a similar improvement.
This is in addition to changing the springs front and rear to a rate that matches your weight.

Next is lighter wheels which will improve turn response. Such as Marchesini, BST, Carrozzeria, etc.
Going from a 190/50-17 to 190/55-17 tire will also improve turn response and is the cheapest option so far.

Beyond the tires, none of the other options are cheap.
Anywhere from several hundred for the exhaust to over a thousand for the suspension or more for the wheels.

It's one of those things where you plan, save, and shop around for the next improvement.
How well do I know...
 

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Excellent and informative advice from SubSailor again :)

Following the weight loss idea, you can also remove the Honda PAIR system, which you really dont need and is quite a heavy unit. Its also a free mod :)

The exhaust emission control system consists of a secondary air supply system which introduces filtered air into the exhaust gases in the exhaust port. Fresh air is drawn into the exhaust port whenever there is a negative pressure pulse in the exhaust system. This charge of fresh air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocarbons and carbon monoxide into relatively harmless carbon dioxide and water vapor. The PAIR system is controlled by the ECM using check valves and a solenoid.
Removal of the PAIR system will yield three main benefits: 1) weight reduction 2) reduction of engine compartment clutter 3) increase in the scavenging ability of the exhaust system.

(info courtesy of Rouge Website)

Full removal guide here: http://www.rc51.org/pair.htm
 

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drop in a k&n or similar type filter. thats fairly cheap to do. you can also go with a single sided exhaust vs. the duals which will be cheaper and less weight due to only having one can. you can even mod your existing pipes to a single if your good with a cutoff wheel and welder also look into a 520 conversion kit with aluminum sprockets. saves weight and on ebay can be bought for around 120-150. your best bet is what we all do. just do it a part at a time
 

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drop in a k&n or similar type filter.
I wouldn't

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

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

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.

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.

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!
 

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I wouldn't

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

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

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.

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.

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!
dont believe everything you read on the internet. have you ever actually looked at the stock filters you can barely blow through them, they are overly restrictive. you just read an article from somone opposed to air filters. next youll be saying that exhausts do nothing either due to a loss of back pressure or something crazy like that.
 

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dont believe everything you read on the internet. have you ever actually looked at the stock filters you can barely blow through them, they are overly restrictive. you just read an article from somone opposed to air filters. next youll be saying that exhausts do nothing either due to a loss of back pressure or something crazy like that.
Actually I have some experience of this. I had a pre and post dyno run going from stock Honda filters to K&N's.
Admittedly, I didnt have a commander at the time, but the result was a top end increase of just over 1bhp with the K&N's, but mid range was all over the place, to such an extent that I put the Honda items back on and put the K&N's on Ebay.
Consequently, I went with the TurnOne airbox and Power Commander set up.

The quotes from my last post were courtesy of Rogue, it just explained it better than I can, what I have experienced first hand.

So, you may possibly gain top end, but without proper set up using a power commander or the like, you could mess up mid range. Even then gains may well be minimal, and certainly not, in my opinion, worth the cost of the filters, dyno time etc.

As for your exhaust comment, well thats just absurd lol! Its well known and documented that losing the standard exhaust (in most cases) is well worth while, even if there are no appreciable power gains, each standard exhaust on the RC51, weighs as much as a GSXR, so at worst, you lose weight off the bike. Having said that I have seen some exhaust designs for the RC51 that have been shocking and appear to have had no R&D at all, and quite frankly I'd rather have shoved wasps up my arse than fit said shocking exhaust's :D

Im not a racer, or a track day addict, Im just a quick street rider, and in my humble opinion and from experience, the K&N's were a waste of time and money for street application.
 

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What would be needed is numerous dyno runs testing various filters to approve/disprove the hypothesis.
I did read such a report on a UK magazine, but the bike was not an RC51.
The best filter they found was the BMC Race filter. However because it sacrifices some filtration for air flow, they felt the regular BMC filter was better.
The K&N did have a performance boost over the stock filter, but less than the BMC.

That said, that bike was not an RC51, so the data is not pertinent.
 

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the title of your thread is "help make me go faster" so with that said spend your money on "riding lessons" and what is meant by that is sign up for a race school of some sort that is near your area(and lose weight if you can afford to), and get as much tracktime as possible.

now, if the title of your thread was "help make my bike go faster in a straight line" then that is a whole new ballgame. get a pcIII,higher flowing exhaust, aftermarket airbox, custom dyno tuning, of course perform the flapper mod, pair mod, and soft rev mod, along with 15/41 gearing on a good 520 chain. after that, get some aftermarket wheels and try to lose as much weight as possible anywhere you can on the bike.
 

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the flapper mod is the removal of the flapper from the snorkel, along with associated parts. in the snorkel of the bike there is a butterfly that closes at a certain rpm to limit the noise of the bike for epa reasons. you can remove this and it helps get rid of the dip in power in the mid range of the bike. it can be done for free, or you can buy an inexpensive kit to do it.

as for the soft rev, the US spec rc51's have a soft limiter that kicks in somewhere around 9200rpms (forget exactly where) and then the bike slowly loses power to approx 10,200rpms (again, i forget exactly what rpms the hard limiter hits). removing this allows the bike to make power steadily up to the hard limiter and this increases overall hp by roughly 5whp.

http://www.rc51.org/valve.htm
http://www.rc51.org/b2a15.htm

check out the rogue site as it has some great information there.
 

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no problem.
 
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