CBR 600RR sputtering at 10g rpm

i have an 03 600rr which runs like a champ but lately when i pull down on it when it gets to about 10000 rpm's to 13000 rpm's it stutters and loses power.  it does it every gear but only at that RPM range. Any help is needed  

what mods do you have??  

just have a yoshi rs-5 and better plugs and intake no power commander or anything like that.  

What do you mean by "intake"? Just an aftermarket air filter?  

ya jsut an after market filter. bike has problems starting now...! if its not one thing its another  

Sounds like you've got a fuel pressure problem. You should drain your fuel tank and check the fuel pump screen for debris.  

did the problems start after the air filter or exhaust was installed? if so it,s running lean and will damage your engine. if the bike is injected it will need a fuel management module re: power commander ect if it is carburated it will need to be jetted. let me know if the above items were previously installed and the bike ran ok and we will start again.  
There are worse things than death cowardice is one of them.

'03 CBR600RR is fuel injected, all CBRs were EFI ever since the F4i in '01.

The stock exhaust flows so well that even installing an aftermarket exhaust with an accessory air filter in the airbox will not cause the bike to run lean enough to not run cleanly (while it might be a tad lean, it won't be enough to cause damage)...you will gain power, however, by dialing in the fueling curve with a Power Commander or other similar piggyback fueling device that allows both leaning and richening of the fuel curve.  

So a full race exhaust and a k&n won't lean the engine out enough to cause damage to the engine on an injected bike or cause it to run lean enough to loose power on the top end?  I have Rebuilt many customers engines with the top end burnt down do to running lean under these circumstances on carburated bikes, given enough time any lean condition will result in damage will it not. The E.C.U on injected bikes is designed to make small changes to the fuel mixture in response to air tempeture and elevation demand ect, it has maximum Parameters and as far as I knew can't make up for the lean condition created by a full race exhaust with no cat. Now on a bike with a cat. conv. you can get by with slip ons ect. I am a motorcycle mech. and am interested to hear what you have to say Kento, Should I tell my customers to quit buying fuel management systems unless it is for the performance gain. I am not trying to be obstinate I am confused by your statement.  
There are worse things than death cowardice is one of them.

No, not saying that at all. What I am saying is that the stock exhaust systems on modern sportbikes like the CBR600RR flow very well, and you're not going to get enough increased airflow with just an aftermarket exhaust (and even an accessory air filter for the airbox, because you can't force more air in if it doesn't want to come out quicker) to cause an overly lean fuel mixture. Yes, in some cases it might be a bit lean, but not enough to affect actual combustion and cause rough running (and engine damage). The majority of aftermarket exhausts (slip-ons and even 3/4 slip-ons) are designed with no piggyback fueling device in mind, because they know that not all customers are going to want to spend the extra money to get one. Even the full exhausts don't specify any requirment for a fueling device; they might recommend it, but not require it.

With a completely stock engine other than an exhaust and air filter, you will get the best power gains overall with a piggyback fueling device, but it's not something that will cause engine damage if you run without it.  

Thanks, I get it preferable not required. I am an old guy you know how we are, it has to be perfect if there is such a thing. So I think I will still recomend the correct set up, agreed? I always ask people what they have done to the bike because if the problem started right after the mod. you can almost bet the farm something ain't right. Thanks again for your Patience.  
There are worse things than death cowardice is one of them.

No worries, you're imparting knowledge as well. Troubleshooting is a fairly easy deal when you understand how the motorcycle works.

Yes, it's always best to have a fueling device such as a Power Commander that can alter fueling in both directions (lean or richen). Many of the smaller fueling boxes can only add fuel, they cannot subtract fuel, a key disadvantage.  

ok so i have completely drained my tank, also fuel filter and injectors were replaced before i made the change in gas i have quit using this "new" 10% or less ethanol fuel.....BIKE RUNS LIKE A CHAMP AGAIN. Found a place with no eth. and havent had a single problem. No matter what the octane the fuel ethanol was killing it.  STAY AWAY from it if you can. There are still stores or fuel suppliers who sell no or minimal ethanol fuel and its came out to the same price but you can even smell the difference. thanx for everybodies help.  

I don't believe the fuel is what made the difference. I think by you draining the tank dry and cleaning it I'd what help clear the strainer from the fuel pump.

I am having the same issue