HELP! Strange Fault Code 2500 rpm

Hey guys,

I'm new here and I have been trawling the forums to try and find the answer to my question (so sorry if it has already been covered).
My thundercat developed a misfire so went off to the garage, I received it back a couple of days ago so though I would swap out the SV650 and give the cat a run out on my commuter run.
This morning on my way in (once the engine had warmed up) I noticed the fault code 2500 rpm? and after spending the last couple of hours trying to find what fault code means I have drawn a blank
So I am calling on anyone for help

There are only two fault codes: cycling between engine speed and 8,000 rpm = fuel level sender error and cycling between engine speed and 3,000 rpm = throttle position sensor error.