hi. i could work on the bike today apart from ignition coil readings i visually examined the spark at #1 plug. it had a blue/purple color spark.

since i had a strong fuel smell at idle i reduced my pilot screw settings by another 1/4 turn. after that all 4 cylinders were working and RPM was quite steady. there was no strong fuel smell and throttle response was ok too. sometimes RPM needle hanged a bit when it was returning to idle. i kept this setup and ran until radiator fan kicked in. as engine got hot RPM became a bit more unstable ( fluctuating ). overall it was better than the previous setup.

also i have experienced these two things even prior to the carb clean. these are not major concerns but i forgot to mention them before.

1- if i pull my choke lever gradually while it's idling, the RPM decreases and ultimately engine stalls. this happens in both cold and hot engine conditions. does this indicate a rich mixture at idle ?

2- after a ride if i try to start my bike again in 4-5mins, i always need to give some throttle and then press the starter button. otherwise i have to press my starter button 2 or 3 times ( if i don't give some throttle ). does this indicate some issue ?

i'm planning to ride with this setup and then check spark plugs. will update. thank you.

 

It sounds like you are making progress. Those symptoms do seem to indicate a rich environment. Pulling the choke lever naturally does make it richer. @hamlin6 might chime in here on how his F3 does after it's warm. There is a procedure for adjusting the idle mixture. It's a bit challenging to do since it's looking for drop of about 50 RPM which is not much. I tend to notice that much fluctuation just in normal operation.

 

From cold I always have to use the choke no matter the season. Using the throttle has no affect until she’s running.
after 30 seconds or so I slowly decrease choke until nothing. I then let her idle for 2-3 minutes before putting her in gear.

as to the other, once the bike is warm and shut off for 5-10 minutes you should be able to start the bike with zero choke or throttle.

All this is dependent upon the idle RPM being set to 1,200, while the engine is warm.

How is your idle rpm looking?

 

Those of us who are old school and raised on carburetors have a tough time with not working the throttle when we start an engine. Old habits die hard. Carburetors on many engines had something called an accelerator pump. It would put a little squirt of fuel into the throat of the carburetor as well as set the choke to on. Well, CV carburetors like we have don't work that way. Our motorcycles were designed to start when they're cold with the choke lever pulled, or with it not pulled when warm. Choke though, is not an accurate description of how it works. It is an enrichment circuit, not a choke. If you move the throttle while starting, you reduce the effectiveness of the starting circuits. The tiny holes located next to the throttle plate are designed to have air flow into them while idling and starting, and then be part of the fuel supply when just coming off of idle before the main jets come into play. If you're working the throttle while starting, it's not helping. If it only starts that way, then probably pilot screws are not adjusted right.

 

@hamlin6 thank you. manual recommends 1500 RPM for idle
@IDoDirt thank you. very useful info. i paid much attention to idle circuit while cleaning since it has tiny little holes ( idle port, bypass holes, idle jet port, idle air jet ports ).
yea i've practically experienced it. for instance choke has more effectiveness when we press starter button while throttle valve is closed. i think the more we open the throttle valve the more it reduces vacuum at idle port / bypass holes.

today i went for a short ride 50km+ for the first time after my carb clean ride feeling was quite smooth and throttle response was nice. cold start was good and no strong fuel smell. in cold start i felt a small lag when blipping the throttle. but it went away after a few minutes.

idle was staying at 2000 RPM after the ride. so i reduced it to 1500 RPM which is my manual recommends. rev dropping was fine. it only hung a bit at 2000 RPM and then dropped to 1500 RPM. sometimes has a small fluctuation with that uneven engine sound at idle.

i think it's better to check valves and proceed from there. but for now will ride with this setup and check the plugs. will update. thank you so much for your continuous support.

 

Good deal on the 1,500 RPM. Follow what the manual say’s for your model.

Remember, if you do need to change the valve clearances you will need to rebalance the carbs. But you now have the hang of it so it shouldn’t be a big deal.

 

If I can offer some troubleshooting advice, while focusing on where the bike is having issues in regards to RPMs is a common thing to do and is usually ok. But it can also be misleading.
RPMs are a result of something and can vary based on multiple things.
what I do when I have a head scratcher is while the the bike is at zero throttle, put a piece of tape on the throttle and another on the housing directly beside the 1st piece of tape. Now twist the throttle to wide open. Put a piece of tape on the housing next to the piece on the throttle. Now on the housing but a piece of tape at 1/4th and 3/4ths.

what this does is gives you a visual representation of which fuel circuit in the carb is mainly functioning at that particular time. This will point you in a better direction than focusing on RPMs.

 

@hamlin6 got it. will try that trick. thank you.

 

Here is a diagram that helps to explain what I was talking about.

 

Some other troubleshooting tips.

With the airbox open, while the bike is running watch the sliders. They should move smoothly and uniformly regardless of what you are doing; idling or twisting the throttle. If one sliders doesn't act like the other, start troubleshooting there.

Another thing is to take a propane or mapp gas and while the engine is running, crack the bottle just a bit (not lit) and put the nozzle down around the rubber isolation boots. If the engine revs increase, you have vacuum leak somewhere.

These are pretty low tech troubleshooting tips but will easily give you an indicator of where the issue is located.