Hey Guys - I need some help here and cannot figure this thing out. I have a CBR 600 F4 year 2000. Its always ran very well. THEN, we had our first child in 16, and the bike became neglected. SO here's what happened.
Used stabil and ran in through the system before winter 2015. Didn't ride in 16, but started a few times to keep it from getting horrible. replaced the battery. Didn't ride much in 17, but did take it out a couple times and worked well. Put in new gas and re-stabiled it before winter 2017.
Spring 18 - replaced battery, full choke, started it, per normal process. I let it warm up for 5, 10, 15 minutes, RPMs did not get higher, it sat around 1000-1500 RPMs. I figured whatever so I got on and touched the throttle and it died. Restarted, touched throttle, dies. Restarted, tried to take off choke, dies.
First fix attempt - put seafoam in gas tank. didn't help. put about half the bottle in. didn't help. put in a diff brand carb cleaner, didn't help.
Second attempt - pulled the carbs off and cleaned them. The pilot jets were pretty clean, I could see through them all, but cleaned all jets anyway. Put back together, same issue.
3rd attempt - replaced the plugs. The previous ones were somewhat fouled, but not horrible. Tried again, same issue.
4th attempt - repulled the carbs, cleaned everything. checked the needles, valves, floats, gaskets, diaphragms, all cleaned all ok. replaced the plugs a second time. rechecked the gap. Also checked the wires, got good spark on the frame from #1 cyl. Put all back together, same issue.
5th attempt - drained all the gas from the tank & lines, put it fresh. rechecked the vacuum hoses, breather hoses, fuel lines, fuel pump. all seem good. Try again, SAME ISSUE.
I don't know what else it could be or what else I can do. I've been mulling the TPS sensor, but read the bold warnings in the manual about not replacing them unless absolutely necessary, and I don't even know if that would fix it. Are there other sensor's for idling that would let the RPM's rise while warming up? I read there is an IAT sensor and MAP sensor, but have no idea what those are or what they do. I thought it very odd that RPM's don't increase on full choke even after letting it sit for 45 minutes. I tried adjusting the idle screw, didn't help. I tried resetting the pilot screws on all 4 carbs back to the factory setting. also didn't help. Was there something I missed when cleaning the carbs? I cleaned the main jet, the pilot jet, and the needle valve holder. Also cleaned out the float bowls. I am really at a loss for what could be the fix here. Please help me out with any other potential ideas for fixes! I'll be happy to send more pics if you need too.

 

Man not 1 idea from anyone? I knew I was stumped but I thought I'd get a few ideas on here from someone? Anyone? C'mon guys help me out please! Even if I already tried it or you're not sure, throws some ideas out - think out loud, surely we can all figure this out! Thanks!

 

Are you sure the choke mechanism is operating correctly? Maybe the cable is fouled or snapped.

Not familiar with the F4 and the electronic sensors it has, but on my old Hurricane 1000 the choke was actually a mixture enricher.
If it was running on 'choke' and gave it some throttle it would stumble and die.

Just an idea, worth a quick look see.

BTW those plugs look horrible!

 

^this. Make sure the choke cable is returning properly. It sounds like an idle mixture issue, and plugs look rich. I'd try setting the pilot screws back to factory and see if that makes a difference. If the pilot jets are clean and spark is good, it should at least idle

I didn't realize those bikes had all that electronic wizardry. A TPS could cause the symptoms you describe. I had an old Acura that behaved the same way. I think it's a suspect. Maybe the aircut valve too. They can both cause problems at idle afaik

It's a shot in the dark, but how's the air filter? Can she breathe properly?

Edit - oops I see you've already tried the pilot screw adjustment. Nevermind

 

The second plug from left is way too wet?!? .... check if all 4 cylinders are alive! Also 3 and 4 don´t look right. Recheck if you get a spark at #2 - #4

All the best!

Edit: You didn´t mix up cables at the plugs?
Edit #2: What about float height?
Edit #3: Do exhaust headers warm up evenly?

 

Is the air-box free of debris, ie a four legged friend building a nest near #2 intake.

 

Looks like a vaccum line issue? Are all hoses good with no cracks? I think you are leaking vaccum somewhere, so the engine is not able to suck air properly. The more choke you give the more fouling will occur at idle.

 

Hi, I had the same issue on my F4 - one time, as I rode back from work, it stalled and it just would not start. I tried jump starting, but had no leverage where it was parked as I could not really move it too far, then I and ended up draining the battery. After that I tried cleaning all the battery circuit and connections and finally changing the battery. I managed to get it to start again, but after that it was like yours - it would only run on choke.
I am not savvy in mechanics, more of a logical sort of person, so I had to get it collected and taken to the shop. Sorry I am not very technical: the guys at Waltham Cross Motorcycles said one of the valves was cracked and the air flow wasn't allowing the bike to run properly due to compression issues, as mentioned by ceebeeaarguy; they replaced a couple of spark plugs as well and adjusted the idle speed... when I got it back it was running really well.
I am not sure if it is related, but my one has done less than 15k. I suspect, that, given the maintenance record, even though it has been worked on, it was not ridden for long periods of time.
I have myself an issue where it shuts down after it reaches a certain temperature and, again, I can only get it running if I jump start it, but I hope your issue is just compression/ engine vacuum. Hope this helps! Good Luck

 

check here for yours!


https://www.google.com.cy/search?ei=....0.tXZSEICtFQE

 

Thank you!