idle issue

Hey all, got an issue that I can’t figure out lately. When I put my 1000R in gear and go to mash the accelerator, RPM’s drop and then she stalls. If I gas it she will take off and while driving no problems again until I stop and put her back in park or N and then she does it again. Just changed...

I recently bought this blue beauty with 4 miles on it. Since I got her home, she's had somewhat of a rough idle after warming up a bit. When I go to take off after this happens, it'll fuel knock real bad and sometimes die. Over 1300 rpms, there is zero problems. No shifting issues. No engine...