I know things... A lot of things.
Join Date: Feb 2015
Motorcycle: GSXR 750 K4
Re: Engine Stutters and low rpms
It sounds like it's not firing on all four, both when idling and when under 4k rpm, but then again, if it didn't, I wouldn't expect it to idle at the proper speed, at least not if the K6/7 doesn't have an ISC valve, which I think is the case. Given that it suddenly starter running properly at idle, after you reconnected the ISC, I suppose it's not the injectors, at least not a case of the primaries being gummed up, as they wouldn't be likely to clear up for a few minutes only. This leaves some sort of control failure as the most likely cause, only you're not getting any codes thrown and it's not the IAP.
Have you checked your charging system, or at least checked your voltage at idle and at 5000rpm? Perhaps it's struggling to keep up at lower speeds due to your recent incident. Low system voltage, can cause all sorts of weirdness.