Reply To: Miss and backfire under 5k only after engine warms up – 2009 GT650R
At the risk of being shouted at! 🤐 (as i know this means strip down time) – You may need to re-download the service manual on this forum that matches your bike (i uploaded loads of variations Hyosung made) and use a pocket meter to test every single electric sensor on the bike until you’re dead sure it’s all in spec
Fuel Pump = I haven’t got a conclusion yet but i’d keep an eye on it.
The ECU should be the last resort and it’s not exactly easy to get hold of due the 2009 type you have as Hyosung has moved on to 2014+ delphi systems. Though, if your bike starts and runs, i suspect to try and at least measure every sensor on the bike 1st before forking out money for another ECU.