Hi I've already posted about the poor running I'm experiencing with my 2001 xvs650 I've tested the TPS and wiring and refitted and set up the TPS and I still have the same issues it also does the missfiting and putting engine light on when revving it when stationary any ideas?

Someone else had this same problem on there 650. They disconnected the battery for an hour to reset the system and it worked. Try that