Hi All,
I have a CBR600 F3 and have a problem with starting. I should say that I bought it as a non runner to give myself something to tinker with, so any problems leading up to this are unknown!

It will sometimes start if I let the starter turn to engine over for maybe 10 or 20 seconds. When it does start it sounds like it is firing on all 4 cylinders, and all 4 exhaust pipes get hot. However, it won't rev above 2000 rpm - the throttle doesn't do much when twisted from closed to fully open... the choke does make a moderate difference. I've taken the air filter off and checked that the throttle sliders are opening, which they are.

As this was a bit of an unknown to start with I've checked the cam and ignition timing, which are OK, put new spark plugs in and there seems to be a good spark. I also put fresh fuel in the tank.

I'm tempted to strip the carbs but before I do I wonder if anyone recognises the symptoms as there a a few ancillaries which I suspect could cause this?
thanks
Steve

 

You're inclination of the carbs needing cleaning is probably the best place to start. The carbs on these bikes are very finicky so it's not going to hurt anything.
There are scores of threads on here to referring to carb cleaning. That should get you started and as always if you need pointers, just give a shout.

 

as above. strip the carbs, and give them a good look over.

find a manual, and make sure everything is set to standard specs, as who knows what changes have been made by others.