View Full Version : WOT running rough
Sup yall,
I own a '95 CBR F3. the bike sat in my garage since May, ever since I started school again. I tried turning it on the other day and it wouldnt idle or stay on without the choke on. so I changed/cleaned a couple of things. It has new plugs, new battery, cleaned out the carbs, I took them out and cleaned them and I also cleaned out the air filter with a KNN filter kit. I fired the bike up and now it turns on, idles well, even fires up without the choke on. great, im happy about that, BUT, if I ride it and I try to go full throttle on it, the bike gets really rough and it just hesitates to go. and it just sounds like its boggin. if im running low speeds, it has no problem, but I soon as I go wide open, it doesnt really go. I might just make a little video of it so ya can see what I mean.
but just from this description, does anybody have a suggestion?
Leon?
shit, I just read the SeaFoam thread on the tech section....
Im gonna be trying that out this weekend. ill post back results.
Mr Lefty
11-15-2008, 04:09 AM
yeah Sea Foam is the SHIT! give it time to work though... and I'd do a few tanks run through of it... add like 1/8-1/2 bottle per tank.... depending on how bad things are... you should be good to go by the time the bottles done.
the only thing is... you've already cleaned the carbs... so you may have other issues... did you get the carbs sync'd properly? :idk:
yeah, carbs were done correctly.
I was watching the video and it was saying to add the seafoam directly to the carb.... I dont want to go through all that hassle, can I just add it to the fuel and let it run through??
Mr Lefty
11-15-2008, 05:18 AM
yeah just pour it in the tank. sea foam is weird... you can pour it in the tank, in the carb, in the intake... even in the oil... good shit!
Gas Man
11-15-2008, 06:01 AM
Yeah I was going to suggest seafoam... gee, its almost like I made the other thread... hmmmm
And Ebbs asked about syncing the carbs. Please forgive me, but you never said anything about that. Its not just cleaning them. So did you actually sync the carbs?
What about the gasoline in the tank? Is it old?
Also, moving to tech... in Florida don't make much sense!
Yeah I was going to suggest seafoam... gee, its almost like I made the other thread... hmmmm
And Ebbs asked about syncing the carbs. Please forgive me, but you never said anything about that. Its not just cleaning them. So did you actually sync the carbs?
What about the gasoline in the tank? Is it old?
Also, moving to tech... in Florida don't make much sense!
I took the old gas out and put fresh in.
syncing the carbs? fill me in on that. Im not a mechanic, I just took the manual and took the whole thing apart, sprayed it with carb cleaning, cleaned them up, put everything back together.
I put it in the florida forum because I am from florida and the question was intended for a group of friends, but I took a look in the HowTo/Tech section after posting and found the SeaFoam thread posted by you, which has great info. :D
but thanks for all the help, if you can guide me on the syncing it would be greatly appreciated.
-Loz
HRCNICK11
11-15-2008, 12:16 PM
Its one of 2 things you either over oiled the K&N and its not getting enough air flow through the filter and will foul out the plugs in time.
Or you did not reconect the the float vent. Your bike has ram air and will run like crap the faster you move if the float bowls are not at the same pressure as the intake. These lines are the 3/4 inch lines a that run around in the carb area. You might have also unpluged the solinoid that switches from high to low speed vent. That solinoid is about the size of a fist and has 3 or 4 of the 3/4 lines ran to it. It switches at about 12mph to the high speed vent which is the one thats on the air ox inlet not the 2 at the front of the bike.
My F3 had 38,000 miles on it and my F2 had 42,000 miles on it I know these bikes like the back of my hand and can help with almost any problems you have. I miss my F3 it was a great bike.
the carbs have breather tubes, 1 for each, but those just go out to the open they dont connect to anything.
i might have a clogged airfilter.... the airfilter is the original/paper thing that comes from factory... and I used the KNN cleaning kit which is made for foam ones.
thats probably my problem. but I still want to do the seafoam thing...
HRCNICK11
11-15-2008, 12:42 PM
The small tubes (one on each carb) are bowl drains. The vents I'm talking about is a 3/4 tube should be 2 of them in between the two sets of carbs that vent the bowl. It should go to the solinoid then from the solinoid to the front of the air box and the front of the bike. The ones that run to the front of the bike are often removed along with the solinoid during a jet kit install. as the low spee half of the system is not really needed.
The oil for the K&N filters is thin like water and you will soak into the filter so you only need a small amount. You can buy it at Autozone or napa most of the time. I normally spray it in strips about a 1/4 inch apart and then let it spread on its own. Then when the bike is together go straight to the freeway and ride about 10 miles or so at high rpms maybe 5th gear instead of 6th to keep the plugs from fouling if you did over oil it. Do not let the bike sit at low idle for a long time until you have been on the free way for a while. Once the plugs foul they should be replaced cause they will never be the same again, sure they will work but they will never be 100% again.
o yeah, i know the 2 tubes you are talking about, and yes, they are connected properly. I never took them off the solenoid. just from between the carburetors.
it would suck to have the plugs fouled again, these suckers costed me $25. :panic:
No Worries
11-16-2008, 12:49 AM
At wide-open, the carbs run on the main jet. The only time I've seen a main jet clog was on a GS850 that sat for ten years with a broken petcock. The gas was like syrup.
On your Honda, and just about every other carb, the jet needle pulls out of the main jet as the diaphragm/piston rises. On my old GS1000, the throttle cable controls the rising brass piston. But after 1980, the plastic piston rises due to the vacuum of the engine.
That piston, and the walls that the piston rises in, has to be squeaky clean for the light vacuum to lift the piston out of the main jet. I don't know about your 600, but on my CBR1000, I can pull the airbox back and lift up each piston in the carb with my finger. There should be light resistance, and it should fall with a plastic thunk when released as there is a light spring under the piston. If all four don't do that, you will have to take them apart and clean them.
I don't know how mine get so dirty with varnish, as I have to clean them twice a year. But when they are clean, the throttle response is instant.
Gas Man
11-16-2008, 01:00 AM
Come on NW... you are a sync'ing master.... speak it to the guy.
The basic gist is that it ensures that all the carbs are delievering the same amount of fuel all the time.
No Worries
11-16-2008, 01:14 AM
Come on NW... you are a sync'ing master.... speak it to the guy.
The basic gist is that it ensures that all the carbs are delievering the same amount of fuel all the time.
You're right. I always do a sync after the carbs are running right. But his ain't. Plus, it's a Honda. So the ignition timing should also be checked since the advance is electronic.
Speaking of ignition, My GS1000 had points ignition before I changed it to a Dyna electronic ignition. But that's just the trigger. The ignition advance is still done by the old weights and springs. I have to oil them every five years or so to keep them working smoothly.
I havent used the seafoam yet, but I did buy a can of it. I turned on the bike today just to see if it was idling a little better and accelerating better and it was. I open the throttle all the way and it didnt bog or ran rough... my guess is probably that the air filter was still moist and the the application of oil that I put on, it was probably a little bit clogged. but it most likely dried up by now.
here is a little video.
http://www.youtube.com/watch?v=KhcFGH8BOgQ
I will add the seafoam tomorrow and make another video.
can someone point me to a tutorial on sync the carbs?
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