This is my first 93 Honda CBR600f2. I got the bike two weeks ago. It was running great but had a leaking vacuum valve on the petcock. I got a rebuild kit for it and rebuilt it (CoverSet ****). I know for a fact I rebuilt it the correct way. Two days later the bike was not firing all four cylenders. Got new plugs and replaced them. Ran awsome for a day and then the next day would not start. The bike smelled like gas heavely. So now I have the carbs off and the valves look good . . . I think, I re puled the plugs and all but #2 plug look the same #2 plug looks white and burnt the rest are dark black. What the heck did I do? This is my first bike. I am a Novice but not dumb. Are the valves suposed to be all up or all down? Should they alternate? I dont have the money to go to a shop and dont have the tools to go any further. I would really like, like any one would, want the bike to run ; Any ideas? I have a manual for the bike any thing in there that would help me please point me in the right direction. Just one more thing. I took the petcock off and with it in the off position when I blow into the tube that goes into the gas tank air still pass through. Is gas getting in the carbs and flooding?

 

check to make sure the diaphragm is installed correctly, it can be easy to install backwards, also the vacuum line to the petcock is connected to the number 4 cylinder and it uses the pulsing vacuum of the motor to open and close the petcock, allowing fuel to flow, the carb float levels may be incorrect, if you look in your manual youll find a fuel float level specification in book, and you can purchase a float level meter for cheap, its a small hose with a glass tube and measurements on it, you connect it to the drain portion of carb with carbs installed on bike, and hold glass tube level with there the carb float bowl meets up to carb body and read the measurement the manual will describe it all in the fuel section. you might want to get a compression tester as well to make sure compression is good, manual will have exact spec. also make sure your carbs dont need to be cleaned or synced, do you know if bike sat for a long time before you got it?

 

I'm not sure if the bike sat. But like I said it was running great until I replaced the leaking vacuum valve. Thank you for your help.

 

ok first things first, pull the vaccum line from cylinder 4 (the one that runs to petcock) but leave it attached to petcock, turn fuel valve to on or reserve, pull the fuel line and let any fuel in the line drain out, then i want you take the vaccum line and apply a vaccum to it, you can apply vaccum with your mouth and then us pliers to pinch line, once vaccum is applied fuel should come rushing out! so make sure you have a suitable container to catch fuel in, once vaccum is released fuel should stop flowing, make sure you put the fuel petcock **** back on correctly as well.

 

So did this and it seemed to be working. I have checked the carbs and they are clean as a whistle. I drained the oil and it smelled like a gas oil mix, any idea why? Also I drained the coolant I look like there might have been oil in it but the way the oil was smelling with gas the coolant did not smell like that . . . So I think the coolant did not have oil in it. I did a partial coolant flush, partial cuz I did not have the bike running when I did the flush. I will do a full flush when the bike is put back together. I also had a leaking oil cooler gasket. I have ordered a new one so Im waiting that part. I puled the plugs again and they look fine.

 

usually on a vaccum operated petcock like that it wont fill the crankcase with gas, usually only if theres an issue, since you changed petcock already i would just change the oil and filter, plugs if they are ok should be fine, have you checked for a good bright blue spark on all 4 cylinders? also hows your air filter look?