This is my 1st post on here, and 1st of all would like to say great forums! Have read thru a bunch of posts from people who have similar issues to my bike and have read a lot of great advice on how to fix it.
With that being said, I still haven't managed to fix it

I have a '99 CBR600F4 which has the following symptoms:
Will only start fully choked, even when warm.
Won't idle unless fully choked.
While fully choked I can't rev the throttle or it stalls.
Once its warm I can sometimes take it off choke and get the engine to rev. But if I stop revving it stalls.
I have hesitation in all gears when giving it gas.

Steps I have already taken to resolve the issue:
Have taken apart the cabs 5 times now and cleaned them by boiling them for 2 hours and then soaking them in seafoam for 24 hours. Blew compressed air thru everything. However I did not remove the jets as I don't know how many turns they are supposed to be.
Have synch'd the carbs to the best of my ability, since it won't idle steadily I get different readings at different rpms.
Have used a multimeter on the regulator/rectifier, which at the battery showed 14.5-14.8 volts at 2000 rpm(can't rev the bike up to 5000 due to stalling)
Have tested the resistance to the stator which was .566 across all 3 wires. Did a reverse test which came up 0
Fuel pump seems to be working fine as it pulls gas from the gas can I have sitting next to the bike.
Also at some point the Evap system was pulled from the bike and I dont know if its been bypassed correctly.

At this point I have no idea what else to try, so any help would be appreciated as I am just learning how to work on bikes.

 

Sorry you're having the issues. Do your research & find out if it indeed was done correctly.

How did it run when you bought it & what has changed?

Be sure to follow the flow chart in your factory service manual for trouble-shooting.

 

Well bit of history on the bike and I will start off and say I was an idiot when I bought it.
Got the bike from a cop in Tracy CA, so thought I could trust him when he told me bike was mechanically fine and that it just need carbs cleaned. Paid 2k for the bike rode it home and it was backfiring blue flame out the tailpipe. Brought it to a mechanic who told me something is mechanically wrong with the carbs and it would cost around another 2k to fix the bike, tho they basically refused to work on it and said the bike wasn't worth 300 bucks.
Tried to return the bike and the cop told me sorry you bought "as is". Since then have been doing what I can to try to learn to work on the bike.
Only thing I have managed to improve over the last 2 months of working on it is that is no longer backfires.

Last night I took the pilot and main jets out and have them soaking in seafoam now. Although I have no idea how many turns I am supposed to have them and I dont know if that means main jet or pilot jet or both.

As far as the carbs in general go, I cant see anything obviously wrong mechanically with them. Only thing I really noticed was the jets were fully screwed in very tight and I remember reading a post on here they they are supposed to be turned out a certain amount of turns.

 

Sounds like its starving for fuel, have you checked out the fuel tank and filter etc?

 

I was debating bypassing the fuel pump as a test, but I need to look up on how to do that so haven't done it yet. However from what I can tell the pump seems to be working as I have a gas can with a hose in it and it pulls gas from the can. If I get it running again tonight, I'll take some pics and vids and post em. Might help with some diagnosis.

 

Ok this is what my carb pilot screw looks like:



This is supposedly what its supposed to look like:



Also finally managed to locate the spark plug puller tool and pulled one of my plugs which looks like this:

 

Well since I have seemed to have stumped the lot of you

I decided to throw money at the issue, bought a set of carbs off ebay, a set of spark plugs, new air filter, and the sigma 6 custom jet kit. Hopefully everything will arrive before this weekend.

Over the weekend I did manage to finally locate the info on the jets and pilot screw. Reassembled everything and managed to get a pair of tweezers to fit and turn the pilot screw out the required amount of turns while the carbs were still off the bike. Gave up and bought everything when I found out I have to adjust the pilot screws while the bike is running as there is no way I can get down in there with tweezers while the carbs are attached to the bike, plus my gf is pissed I bent her good tweezers

So hopefully will get to work on the bike this weekend and if the issue was the carbs, hopefully the new carbs will fix all my issues.

 

Not a matter of "stumped" as it is difficult to assess complex mechanical issues via interwebs based on brief descriptions of what may or may not actual be occurring. ;-)

Nevertheless, hope you solve your issues.

 

Sorry was I just kidding around about the stumped part, hence why I put below that I gave up and bought everything when I found out I had to adjust the pilot screws with the carbs on and bike running. At that point it was just easier to try with a set of carbs that hopefully will not need the jetting adjusted.

Hopefully with a little luck I will have the bike up and running by Sunday and can stop putting so many commute miles on my 954.

 

Oh, no worries DJ...just givin' a retort. Thus, the smilie face. ;-)

All joking aside tho... At times, I've helped work thru issues w/ new F4 owners over months...yes - months...only to discover that they've been describing the problems incorrectly, not performing so-called 'repairs' properly, etc. Not saying that's your case but just giving you some history on why I answered it that way. :-) We really do our best here to help where we can but sometimes issues simply can't be absolved via interweb due to the inability to verify the actual issue of what may or may not actually be occurring.

Anyway, really sorry that you're having the problems. The seller was less than forthcoming w/ issues. Shame that you had to start your F4 ownership on this note. F4's really are great bikes if properly maintained. However, so many new owners purchase F4's that have been neglected or mistreated & then have problems due to that. I'm hoping you can get everything sorted asap & get to using it for fun & everyday use.