81 KZ1000 hesitation from stop to start

Just about finished my custom KZ project.

Current jet 40/140, 2 turns out. K&N pods and stock exhaust with the baffles cut off. Carbs are vacuum synced.

The issue is that I have having some "sputtering" or hesitation on the initial GO. But once above 2 or 3k rpm the bikes mid-high is awesome.

Where should I start my adjustment to get my low where I need it?

fixed it by using some thin gauge steel plate cut to fit the opening of the exhaust pipe. Then drilled a single hole through that.

I am having a similar issue, So just for my own clarification, you increased the back pressure on the exhaust and that fixed it?