Hello, i recently bought a 1998 cbr 600 f3. I am 18 and a rookie at the street bike stuff, but ive worked on dirt bikes and cars for a while, so im not some dumbass teenager LOL.

When i bought it, it had been wrecked and had some cosmetic damage, but it ran awesome. I rode it 2 or 3 times and it every time i pinned the throttle it would scream to the red line in no time at all. I ordered some fairings from auctmarts(Which i was extremely impressed with btw, the paint job and fitment was awesome) and took off the gas tank to have it painted to match the new gas tank. The process of getting everything back on and good to go resulted in the bike not being started for 3 weeks. I got all the new stuff put on and filled it up with gas and tryed to start it when i got home, the bike would not start all it would do was white smoke and back fire. It turned out i had gotten some bad gas with a good amount of water in it.

So after reading different forums and stuff and picking up some pointers, i FINALLY got the bike running after I:
Replaced spark plugs
Cleaned carburetor
Flushed fuel lines
cleaned and recharged K&N air filter
I filled up the gas tank with some Chevron Mid Grade gas, and poured about 4 oz. of B12 in with it. The bike ran rough, continually back firing, but after the B12 passed through and i filled up the tank again, it smoothed out. It will start up pretty easy now, i just have to crack the throttle a tiny bit for it to start. Once i get it started it will idle smoothly at 1,200 rpm. So i thought it was good to go and i had fixed it.

However, today i took it for a ride and it would run alright until id give it some hard throttle, it will SLOWLY climb up to about 6,000 rpm in each gear then just bog down like crazy. It is NO WHERE near the power i had when i first bought. The bike is in the shop now, they are replacing the wheel spacers and putting on a new rear tire. When i get it back (hopefully tommorow), im going to reclean the air filter because i might have put too much oil on it and see if that has anything to do with it.

So, i am wondering what some way i can get it too quit bogging down and start operating past 5,000 rpms. Thanks for any help in advance, Rider

 

too much oil on the filter can restrict the air flow. clean it again, or just remove it and see if it solves the issue.

be aware that most running issues with carb bikes are usually caused by a carb issue.

 

Also post up some pics with the new fairings.

 

I cleaned and re oiled the filter, this time with a lot less oil and it runs a lot better, thanks for the suggestion Daemon

 

Youre welcome. Glad it was something simple!

 

Its still not pulling as hard as it was. It would get 0-60 in prob like 4 seconds before, now itll take probably 6 or 7 seconds. But i still havent really wrapped it out yet since i got the bad gas cleared out, so ill ride the **** out of it and see if that cleans it up

 

Hey there,
Just a thought, because I just (litterally) had similar symptoms. The bike was hard to, or wouldn't start. It backfired and popped as I tried. This bike NEVER needs any more than a push of that button to start (choke on when cold). I left it for a couple of days (angry), then she started right up like normal! Long and short of it... the fuel pump wasn't working. If I left it long enough, fuel would fill the bowls and it would start up fine. It's an easy check. The pump should "thump" while running or turning over. If not, it's not working. After following the pump testing procedures outlined in the Hayne's manual (to verify), I picked up a 30 dollar "fuel pump switch" rebuild kit. Thanks to a How-to thread by Idodirt https://cbrforum.com/forum/stickies-...l-pump-102151/ I had it rebuilt and reinstalled in about 30 minutes! Runs great now.
Keep us posted!

 

Oh yeah,
and if you do a search on fuel pump in this forum, you'll find some people with similar issues above 5000rpms or lack of power in that range. It was due to a malfunctioning fuel pump. May or may not be your problem. Just thought I would mention it.

 

You should hear a thump when the bike is running?

 

Absolutely. You should feel and/or hear that pump running. Put a couple of fingers on it, and you will definately feel it "thumping". If you can't feel it, it's not running. You might want to try this... Start the bike and warm it up to idle. Then shut the fuel valve off. Within a few seconds, you will definately feel that pump "thump, thump, thump". The reason I suggest shutting of the fuel valve, is that the pump will stall a bit when the carbs fuel bowls are full (need/float shut). Though you should still feel a regular "thumping" (lol) as it runs, even when the fuel valve is open. Just saying, it will come alive quicker if the carbs empty out a bit.