As I am a proponent of the reverse-bleed, you probably didn't perform it correctly. You need to use either a spring-steel clamp or a small hose clamp to hold the short piece of 1/4" clear plastic tubing onto the bleeder valve for the clutch, or at each caliper bleeder. As you push fluid into the opened bleeder valve, you will see the master cyl reservoir begin to fill, probably with dark, contaminated brake fluid. That's good, but be careful not to let it overflow, spilled brake fluid is a good way to ruin painted items. If you continue to remove old contaminated fluid from the master cyl reservoir, eventually you will see the new fluid you're injecting will be clear, w/very little contamination remaining. The bubbles will go from bigger bubbles as the air pockets are flushed-out, to 'tiny, little bubbles' at which point, you can close the bleeder valve. Fan the lever rapidly a few times, bleeders closed, and you should have a firm front brake lever, or a properly-operating clutch.
The Cobra 'slasher' pipes, as you call them, are one of the best-looking and
worst-performing pipes for our bikes. They cost you ~10% or more of the average RWHP you have. The Stage 7 kit does nothing to help overcome the deficit of the 4-into-4 'slashers.' Unfortunately, the only thing you're 'slashing,' is your RWHP! But, your bike, your choice on what to do with it, and how to do it.
If you want to keep the 4-into-4's, I'd remove the Dynojet Stage 7 kit in its entirety, and put it on here for sale, for a couple hundred bucks. Get some money out of it.
Look on here in the search function to compare your Stage 7 needle shape with the comparison chart Sean Morley did. It shows many OEM needles for both the VMax and the Venture, and the aftermarket companies: Factory Pro, Dynojet and others. That way, you can see what exactly you have in the way of 'kit' for your carbs. Take-off one of the CV caps on the side of your bike, remove the slide, and the screw holding the needle in-place. Compare the needle you have, to the ones in Sean's picture. You might be surprised to find out what you have, over what you were
told you have.
Note some needles have several grooves for adjusting the gas mix by placing the internal e-clip into another position. Moving the e-clip towards the pointed end
richens the mixture while moving the e-clip towards the blunt end
leans the mixture.
Here it is, saving you time.
A simple chart of the most-common choices:
Be aware there are
no Stage 2-Stage 6 needles or kits! 
