Hello,

I am having some issues with my 1989 CBR600F and not sure where to start looking for the problems. Here are my symptoms:

1) To start the bike, I have to have full choke on. After about 5 minutes, the bike starts running well (revs go up), so I give it about 1/2 choke to get it idling at a stable rate (about 1500RPM).

2) When I go to turn off the choke, the bike dies, and I cannot start it without the choke on.

3) If I restart the bike with the choke on, and give it gas (throttle it up), the bike dies.

Last year I noticed the bike getting worse, like it would only run when the throttle was partially on. And even then, when the bike was running, it sounded like I was sometimes missing a cylinder.

I have put new gas in, mixed in some Seafoam, and changed oil. But something very wrong when I can only run the bike with throttle on.

Any help is very much appreciated! I have had this bike for 12 years, and really miss riding it this year.

Thanks.

 

i would start by pulling the plugs and see how they look, and make sure you're getting spark to each spark plug. check exhaust pipes with an infrared thermometer with engine running to see if a cylinder isn't firing.

sounds like you might need to clean the carbs. the choke richens it up, you might have a blocked jet. i think its a idle jet, since it runs half to wide open thottle.

 

tripicana,

Thanks much for your reply and information....its much appreciated! Today I plan to pull the carbs and do some cleaning. Here in Minnesota, its finally getting nice to ride, so I'm inching to get out on the road.



The infrared thermometer is an awesome idea, so will try that as well.

Thanks again!

 

clean the carbs, it really sounds like they are clogged up pretty well

 

Everyone,

Thanks much for your help and input. What would you recommend as the best cleaner to use when cleaning the carbs? I plan on taking them totally apart this weekend. Just was not sure what the best cleaner was.

Thanks.

 

go to an autoparts store and grab one of those cans that has a basket in it for dunkin g parts. remove all the jets from each carb (do one carb at a time so as to not get them all confused) and soak them in the stuff for a little while, longer or shorter depending on how bad they are. take them out, use some carb cleaner (any old thing from the hardware store should do) and blast out the jets. follow by using compressed air (an air compressor with a a nozzle on it will do fine) and blow them out one last time. spray the cleaner and compressed air though all th jets in the carbs themselves as well. once it is all reassembled and installed you will want to do a carb sync to make sure it is good. good luck, and let us know how it all turns out!

 

if you soak the carbs in any cleaning solution, make sure you remove all the rubber parts. even carb cleaner will turn rubber into goo if left on to soak. anytime i use carb cleaner, i imediately blow it off with compressed air. if you soak them, you need to completely dissasemble them. there are rubber seats in the chokes, rubber orings in the air screws, the vacume slide diaphram is rubber, and the rubber float bowl gasket.
make sure you keep the parts separate and return to their original position.

 

Tripicana were you using coke for carb cleaner?

 

while I will give the disclaimer that if you try it and it gets messed up I warned you that it could happen.... but I have dunked assembled carbs in the stuff and never had an issue with rubber being ruined. but it is a distinct possibility so if you try it and get a bad result I WARNED YOU!!!

 

lol, no the coke wasn't used as carb cleaner.