Hello everyone, new to the forum, just bought a 95 CBR 600 F3 that wasn't running, the guy i bought it from said it had no spark, said he rode it, then parked it for two weeks and it wouldn't start anymore. Brought it home, threw some jumper cables on and it has spark, but still wouldn't start, sprayed starting fluid and it fired right up, just screaming, so i figured it's fuel related, bought a new fuel cutoff relay, nothing, so i bought a new fuel pump, still nothing, it doesn't seem to be working, i put a volt meter on the relay, the bottom two wires were hot, the top one, i believe blue and black that goes to the fuel pump was i think .17 volts, so i unhooked the fuel pump and put the volt meter on the plug and it was the same, around .17 when cranking and then when i let off it jumps to 2 volts for a second, so i hooked the pump back up, but took off the outlet hose and jumped the wires on the relay and the pump started pumping, so i hooked back up the outlet and jumped the relay and the pump ran for a second and stopped, sounded almosted labored, but when it stopped i heard a pop, and wouldn't do a thing even jumping the relay, then i heard a pop again and it cranked the pump for a second and the stopped again, the popping came from somewhere in the middle of the bike. So i pulled one of the gas lines to the carbs and gas poured out of the spigot on the carb, don't know if that means there is fuel in the bowls or not, I'm pretty confused, i got the relay for the dealer, so I figure it should be good, also the guy i bought it from ripped out the airfilter, and was driving it that way, wondering if that put excess stress on the fuel pump and maybe burnt up some wires in the harness? The bike has been laid down, but not real bad, just torn up the fairing, and i don't have the gauge cluster hooked up if that matters at all, but I'm stumped, does anybody have any ideas? Thanks in advance for any help!

 

Have you tried bypassing the pump altogether? Just run a hose from the petcock straight to the T hose connection that splits to both sides of the carbs. If it has the same problem, then you know it's the not the fuel pump (could still be faulty, but it'll help sort out the problem(s)).

 

It sounds to me that you have blocked carbs. Id suggest taking them off and cleaning the jets...... also get a replacement air box for it as it is there for a reason, it also contains air filters to stop **** entering the carbs.