Hesitation, lag at 5k, then massive surge

1994 seca ii, stock pipes, stock intake.

Sputters up to 5-6k RPM, then it litterallly stop accelerating, then a massive power surge to redline.
OK so to make it easy, i made these pics, problems are numbered 1 to 5.

 

The thing to do is to spend the time to comprehensively Clean every Part within the rack.

One of the main causes of Irregularities upon Opening the Throttles and making Power is the Condition of the Emulsion Tubes those long Needle Valves fit into.

They can have as many as 24 Air Metering Ports which may be clogged.
The Air from those Ports helps bring-up the Fuel from the Main Jet Supply.

Equally as important is the free movement of the Carbs Sliding Piston.
If the Bore has oxidized the movement will become uneven.
Scrub the Bore with ScotchBrite to its original luster or polish the Bore for performance.

In your case you will also have to test the Fuel Pump.
The Fuel Pump can become clogged and restrict the flow of Fuel into the Carbs.

Find a Seca2 Manual and read the section pertaining to the Fuel Pump.

(( I am NOT sure about the Pumps on Mid-90's Bikes. Some Literature says to remove the Pump and Place a Hose on its OULET into a Container of CLEAN Fuel and FLUSH-OUT the Pump by REVERSING POLARITY to the Electric Motor and having the Pump run backwards. ))

 

To more directly answer your questions:

1: Not good, better get it out and get it replaced.
2, 3 4: Not sure, hard to tell from photos but not "adjustments" anyway. If you're running the stock intake and stock pipes then such "adjustments" shouldn't be needed. I believe those screws you are talking about adjusting simply retain the affected parts.
5: I don't think so.

Rick is right, it sounds like a classic case of pluggage somewhere, probably emulsion tubes. Sounds like it only runs on the mains and sputters until it can get there.

"Adjusting" or "rejetting" is not going to be your fix. CLEANLINESS will save you.

 

If you are able to show us those photos ... you have the Carbs OFF the Bike!

THAT's more than half the fight getting them back to Tip-top Shape.

Don't let the idea of dismantling the Carbs for Cleaning alarm you.
Get the Manual.
Follow the Instructions.

DON'T try and do the whole four in one sitting.
Make a game if it and do ONE at a time.
By the time you get to the forth one ... the chore will be Old-hat.

 

Thanks, I have cleaned them extensively. I did take them all apart, its just those 2 needles I have no clue what I am supposed to do with.
(PIC is just for reference, not my actual carbs)

 

Thanks to those that helped. I full and thoroughly cleaned the carbs. The bike runs like a champion now all throughout the rev range.

The problem was the smaller jet was clogged.

 

Hello:

THOSE Carbs are NO WHERE NEAR Clean.
No way. No how.

The Float in the Picture is Filthy.
Clean = Shines Like NEW.

You got to ToothBrush or Scrape ALL Traces of Crud away.

If those Floats look that way ... I wonder what the Emulsion Tubes look like?

POWER ROBBING DIRT:

 

Thank you for your concern but these are not really my carbs, just a reference picture.


These are mine

BTW that piece you posted up is called an emulsion tube? I thought that was the pilot jet or something..i just want to learn the part names correctly.

 

Emulsion Tube.
Nozzle.

You might see it called either.

The Diaphragm Needle Valve extends down into the center of each.
You remove the Jet and Washer holding it in place and (Push/Drive/Lightly Tap) it out through the Top.

Clean:
Interior diameter
Outside diameter
Each Metering Port.