A problem with a '94 zx9r. Idles on all 4 carbs with the choke on, but when I twist the throttle the engine wants to quit. I am unable to have the choke fully off. New fuel filter replaced. Fuel selector checked out fine. New plugs and wires. All 4 cylinders are firing. Idles smooth. It appears to be a fuel delivery problem. Could it be a fuel pump issue? How about a vacume issue?

Any help would be appreciated...

 

it could be any of them.. but i'd first and foremost, inspect the synch on them..
sounds alot like an off-sync set..
inspect the float levels.. your pump pressure outta be about 3 or 5 psi i think as well.. NOT sure on what the delivery rate per minute is tho..

if you rev it, and it takes a good while to settle into idle, its either a sync issue or a vac leak.

good luck, keep us posted, and welcome to KF!

 

Thanks for the response! I will check the sync also. I'll keep you posted.

Michael

 

hey i own a 2000 zx9r....it ran awesome then just stalled at a stop sign..now it just starts but runs very eratic and stalls...wait a couple minutes and it starts up and stalls again. any suggestions??? could it be fuel pump?

 

Hey on3go has the bike been sitting at all? That sounds exactly like I had w/ my 600 and after replacing spark plugges, filter, getting the carbs checked out replacing air filter (don't know why that would have helped but was at wits-end) I just went out got some carb cleaner and some seafoam for the gas tank. After running it around the block it clearned up and has run great. Just a thought...

 

The bike had sat for about 2 weeks while in the shop for a new rear tire and brakes. I brought the bike home and about 5-10 miles into the ride, the thing started running like crap. I will finally get some time to work on it this week. I'll try your idea before I take it back apart. Thanks AHUFFY.
Kustomxz9r-Did you get a load of bad gas ie; water in fuel? Maybe some crud in carbs? I would check those first...

 

Update...
It doesn't seem to be the fuel pump. The symptoms described above from several friends and the guys here think it is the carbs so I am in the process of taking them apart and cleaning everything. I'll let you know if it works. The mechanics mentioned the ethanol that has been put in the gas since '06 has been gumming up carbs.

 

i have a 95 zx-7 thats doing the same thing yours is mines in the shop right now and they can't figure it out they say it runs mint on a gas i v but as soon as you hook up all the lines and the fuel pump it runs they way you described yours they also replaced plugs fuel filter and fuel pump i'm not sure whats going on.