Im going to try to cut a vent cap and put it on the tube and see if it helps
The cap did not work it started to cut out when I gave it full throttle
I have to ask: Exactly where are you trying (or actually doing) to put this cap?
The plastic offset T joint with the open barbed end between the tops of the carbs is the float bowl vent. You do not plug the open end of the rubber hose that attaches to the barb, it is a VENT and has to remain open.
On the 49 state Sabre carbs, the barb (of the plastic joint) points rearward. The rubber hose attaches to that barb and then it snakes behind the rear cylinder. At the bottom of the rear cylinder, it snakes behind the left rear crankcase chrome cover. There are 2 quick clips with thick washers that secure the top of that chrome cover and a 10mm nutted stud that holds it on the bottom middle. Once the quick clips are pulled and the bottom nut is removed you have to wiggle (if it has never been removed before it will require judicious wiggling force) the cover to get the tapered bosses to come out of their rubber grommeted holes. Behind the chromed cover you will find the starter gears cover (kinda triangle shaped). Below that starter gear cover, tucked up tight to the engine, is where the end of the float bowl vent rubber hose (that comes off of the barbed plastic offset T pipe on the carbs) sits on the 49 state non-emission controlled Sabre carbs. At that location is a vinyl coated bendable hose retention strap. Being behind the chromed cover and tucked up tight to the engine is how the open end of that rubber hose stays out of the air flow no matter what speed you are going.
There are other 'out of the air flow' places on the bike where you can run the end of that open rubber hose. Just be sure that the hose does not get pinched flat wherever you put it.
When you removed the emission controls what did you use to block the open vacuum ports on the carbs. The rubber nipple caps that you can pick up at any auto parts store are made from Buna rubber. Buna rubber does not do well in applications around heat and fuel. You are much better off to
snip a piece of the original hose just long enough to push on the nipple and plug the end with a screw.
I tried to find the jets on Ebay that you indicated that you installed. I couldn't find that jet kit. There is a wide variance in jet sizing actual hole diameter from manufacturer to manufacturer. Each manufacturer has their own standard for sizing and no 2 match up. If what you installed is not genuine Keihin jets, again, I would suggest that you go back and start at a baseline condition and move forward in 1 step increments.
You mentioned that you had removed the plugs to access the pilot screws. There was no mention of if you had checked synch or what the pilot screw setting is at now?
I have yet to tune a set of Sabre carbs that I didn't pull, make changes, and re-install, at least 7 times. But then again, I do enjoy tinkering, and the bike is going to do exactly as I want it to do when I get through.
What doesn't seem to be common knowledge is that the 2000-2007 Honda VT1100 Sabre comes from the factory with 2 degrees more advance than the other 1100 Honda from the same era. That is the reason that companies such as Dynatek did not make an ignition module for the Sabre like they did for some of the other 1100 Shadows. That info doesn't even show up in service manuals. Trying to advance the timing on the 00-07 Sabre further than what is built in will not end well and be wasted time (been there, done that).
With your carbs properly tuned and having a somewhat free'r flowing air filter and exhaust (2 into 1 V&H Propipe being the best) you can expect an honest 5 to 8 HP gain but nothing more.
The Sabre 'performance' can be improved some but with an 8:1 compression ratio and a rev limiter at 6200 RPMs the proverbial 'sky is the limit' mantra does not apply. It was built to be a fine cruiser and that is exactly what it is.