2007 Busa crank, no start


Hey, I have an 07 Busa that I got in a trade. It has always had starting issues but I would be able to get her started eventually. I took it to Waco powersports and they basically took advantage of the fact that I dont know anything about bikes. Once I would get it started it would idle ok, but if dump the gas it backfires and blows smoke. When driving it would back fore and loose pressure around 45 mph and again around 80mph.

I have cleaned out the tank with rust remover, checked the air box for debris, rebuilt the fuel pump, changed the plugs, an replaced the battery.
The previous owner was an idiot and he damaged the exhaust pipe where the header and exhaust connect, so there is a leak in that spot.

I am determined to get this thing running again and I don't want to waste more money at a shop. I am extremely grateful for any help in the right direction