Iv had the carbs completely tore apart. Cleaned them 3 times to be sure of things replaced all the carb gaskets. Made sure the jet ratios we're set to spec along with being synched and balanced . Replaced the fuel filter as well. Checked my air filter. All my lines and hoses are good. Just replaced the spark plugs Ngk CR9EH-9 and denso coils today. For some reason it's still got a slight stutter / misfire/ hiccup . At take off from 1st gear it's choppy almost as if you gotta hold the throttle in a sweet spot to take off without killing it. Then from 1st gear to second cruising rpms it's good rides great through all gears at cruising rpms but in any gear and you go to dump the throttle for a hard acceleration it stutters and hesitates. At idle warmed up or cold it has a slight miss fire and the rpm reads between 1-1.5 and Jumps to 2- Ish every now and then. If anyone has any information or what they may think it could be I'd gladly check into it. Any help is appreciated.

 

- Were carbs ultrasonic soaked as part of cleaning?

- Had hidden secret passages scrubbed out with brushes and PEA-based fuel-system cleaners?

- All bleed holes in jets, emulsion tubes, and carb-venturi poked out with matching gauge copper wire?

- Micro soda-blast everything before assembling?

- Replace all rubbers: pilot-screw O-ring, float-valves, float-bowl seals, fuel-rail O-rings, even slide diaphragms if needed?

- Float height set with final wet-test?


Carb's aren't "easy". If any one of those items skipped, can definitely contribute to exact issues you're having.

 

I find the above response frustrating because its more of a blanket reply than it is helpful. I had a problem with my bike after rebuilding my carbs and it was acting like it was running out of fuel. turned out i had forgotten to hook up a hose and my problem went away. double check you have all non-fuel related hoses hooked up to your carbs and to the airbox, and check that your throttle positioning sensor is set to proper spec at idle and is operating properly. if that checked out, measure your pulse coil with a digital multimeter for proper resistance readings.

 

You are correct, it is a blanket reply. That's because the vast majority of the time people don't understand how thoroughly and meticulously the carbs must be given attention when cleaning and these blanket-type replies are needed. There have been so many times when people swear they cleaned the carbs X amount of times and when pressed for details, it's discovered that they didn't even separate the carb bodies from the rail. So, in actuality all they did was a surface cleaning of things and more than likely destroyed any o-ring or other piece of rubber-based material. If you go back and read the past threads where people asked for advice concerning carb-related issues, most of the time the culprit comes down to dirty carbs. When you combine a bike sitting for a long while with old ethanol-based fuels, it's almost a given that the carbs must be rebuilt. Anecdotal evidence of this is the scores of threads on here and videos on the web concerning the proper cleaning and rebuilding of carbs.

The things you mentioned are equally valid and can cause issues and should be verified. The TPS can and does go bad. Concerning your particular situation, no flame intended but when people are replying to the threads they do make certain assumptions One of those would be that you have your fuel line connected. Again, it's a super easy mistake to make and no ill intent is made in my statement but you can see how someone sitting on the other side of a monitor would think a rough running bike with a fuel starvation issues might think the issue is carb related.

 

I know you aren't intending to flame, I had not taken it that way. I have been working with carburetors for almost 20 years and I understand how crucial it is to clean ALL of the passages. the problem that I have is that not everyone has an ultrasonic cleaner, not everyone has the ability to do micro soda blasting, and asking about float heights is irrelevant to the F4 because it has a non-adjustable float height. in fact, a lot of problems can be solved without micro soda blasting or ultrasonic cleaners. you just have to be able to understand how a carburetor functions, what each part does, and how it affects the way an engine runs.