hello all from oz I have a 95 cbr600 which is a fantastic bike and only my second but i have a problem.
if it is reved and held at say 5000rpm it will suddenly dop a thousand and then pick up again. when riding it is like the bike is surging?
i have replaced/swapped around the coils and the leads seem ok i have replaced the spark plugs but to no avail.
are there any heros to help put me in the right direction?
many thanks from the south island

 

sound like fuel not fire... whens the last time the carbs were cleaned? rebuilt?

 

Is the fuel pump there?

 

thanks guys will take the carby to peaces and give it a clean.Is there anything major to look for etc?
As for the fuel pump is it worth removing it and testing it straight on to a 12v battery?

 

keep it plugged up, but grip it and turn the bike on, it should pulse like a slow heart. if it doesn't its because the pump needs attention be it worn contacts or faulty wiring.

i had a fuel filter that was so clogged it was pretty much killing my fuel pump's ability to pump.

check your fuel lines.