Troubleshooting my Honda CB750F SS's carburetor (need help!)

[Honda CB750F SS]

Whenever I try to switch gears (Gears 1,2,3 &4) I have to consistently double-rev it up just so I can reach the 5th gear. However, when I reach about 80 kph-100kph, it works just fine.

I need help. Is there something I need to fix in the carburetor? or is the problem with a different part.

I would appreciate it if someone can help, as I don't really know much about motorcycles, so I will need the explanation to be very basic.

[CB750Winger]

   Question, what year is your 750 and is there trouble getting it to shift or does the engine want to die or sputter when letting up on the throttle to shift. It could be restricted or plugged jets in the carbs. I would start by getting a can of Seafoam at Walmart or an auto parts store and put 1 oz per gallon in the gas and run it to see if it clears up.

[Honda CB750F SS]

It's a 1976.

There really isn't trouble in shifting gears, the problem is that it seems that I have to double rev just to get it to about 80kph before it gets back to normal.

I dont think the problem is with the carb either, cause it's spic and span. Very clean. Even vacuumed it.

I remember adjusting the air setting, and that's when the problem started.

Also, I noticed that when the motorcycle is on standby and I just rev it on neutral, the first two or three revs are fine, but when it comes to the fourth and fifth rev it makes a gargling sound.

Any advise on this will be greatly appreciated. Looking forward to getting this right.

[cbRider]

Judging by your first post it seems to be a carburetor problem. Like either the accelerator pump isn't working or the low speed or primary main jets are plugged.
Your second post sort of throws that theory out the window.
Question: How does it idle?
Another question: How do you vacuum a carburetor?

Good luck,
Karl

[driving maniac]

did you ever cure your carb problem? my bike a 76 cb750k is doing the same thing.

[Re-run]

Old post here. He may not see it at all.
What yo will want to do is pull the plugs out and clean them. Then run the bike around for a few minutes at low rpm and then stop and pull the plugs again. As long as you do not rev the bike, you should be able to get a good read of your low speed mix. So you check out the color of the plug nose and electrode.

Clean them again and this time, get on the highway and gun it through the gears keeping the rpms up high. Do it in a quit place outside of town You will be speeding some.
Pull the clutch and hit the kill switch and stop while holding in the clutch.
Pull the plugs and check them out. This will be your high speed reading.

We can use these to determine if your engine is running rich or lean.

[kramit]

Carb sounds like starving for fuel-carb may need pilot screws reset. You say it revs good first 3, or 4 times
then you have double pump throttle to get more fuel. When your  driving at higher speeds, and carb bowl fuel starts to empty you again have to double pump throttle for more fuel. If problem started when you adjusted pilot screws try to re-adjust. Everybody seems to set theirs different I have mine at 2 and 1/2 turns out. This works for me I have stock pipes-if 4 in header could be as much as 3 and 1/2 out. As one of the guys mentioned above pulling and checking color of plug. With all these great tips from everybody hopefully you can narrow problem down.

kramit