Alright first off i'd like to say i'm new to the bike scene but so far love every bit of it...now onto my actually reasoning for posting this. I bought a 1996 cbr600 f3 for my 1st bike and well it starts up just fine revs up just fine everything. As I start driving off it does fine up til about 30mphs or 3rd gear and starts lugging like its not getting any fuel and if i put it in 4th,5th or 6th there is not power AT ALL just falls on its face and slows down and if i pull the clutch in and try to rev it up when its doing this it will just stall out. After about 4 months of it being like and sitting in a garage i pulled it out to drive it one more time before i sold it and some how it worked just fine and continued to do so for about 2 weeks and then the other day i went to start it up in the morning to take off on it and wouldn't you know it...its doing the same exact thing as before exactly! Any suggestions what it could be and where and what to look at? when i 1st bought it i changed the oil, plugs and wires. I'm new to the whole carb scene.

 

Sounds like something is wrong with your air valve thing.(dont remember what its called) It switches right around that speed so the ram air works properly.

maybe someone can help clear this up better

 

yeah for those two weeks it worked just fine shifted through all the gears was doing a 75mph on the interstate fine if i really tried to get on it hard though like whine it out it would start cutting out around 10k in every gear. whoever owned this bike before me really put it through hell!

 

There are a few things that can cause this (apart from carbs) As redzintimidator said, the air valve solenoid (but check that the air intake tubes are not bent or obstructed 1st), Air filter dirty (not letting air flow), petrol cap air vent clogged, fuel filter clogged & even the fuel pump could be starting to go (you can bypass the pump & see if that it improves the bog down issue).

 

a single kinked tube (from anything as small as your tank sitting on it) or a tube getting disconnected can cause that.

 

It just happened to me! It was the float bowl tube, i believe its called. There is 2 air intakes....kind of. One that goes thru the air box. But, there is also a hose that should be coming out of the carborator that lets air go into the carbs. Mine needed that hose, and all is perfect now. Hope this helps.

 

ok so today i pulled the air filter out and drove it down the street and it continued to do the same thing then pulled the fuel filter off and drove it with just the fuel line still continued to do it then opened the tank and drove in down the street to make sure it was the vent on the gas cap...still doing it all the hoses to the airbox are connected now what and where exactly is this float bowl tube at? Also how would i know if my fuel pump is going out or not i mean i can drive it all day going 20 mph just anything over 30mph or past 3rd gear it just doesn't want to go anywhere. haven't checked the solenoid yet or is that just something you replace and can't check?

 

Give this thread a look for info on the air solenoid bypass.

https://cbrforum.com/forum/showthrea...ghlight=bypass

 

the float bowl tube i am talking about is a tube that connects to the carbs via the area where there is like 2 or 3 hoses bunched up together, on the side of the carbs towards the seat area, and the other end of the tube should be exiting out of one side on the bike, that comes up either on the side of the tank, or in front of the bike that has a little nozzle on the end, so the air can go through faster i think. I will post some pics tomorrow of mine, and mine was doing the EXACT same thing. look for a diagram of the carbs, and you should see what im talking about.

 

ok good new (: i bypassed the air valve solenoid and works just fine now. It still seems to flat out around 9k though in any gear except neutral i can rev it all the way up to 13k any ideas what this could be. i'm changing the air filter today it was pretty dirty!!! Thanx for the help though now i can atleast enjoy my bike a little bit lol