Hey guys I have had my CFMOTO 650 (here in Taiwan its known as a Hartford Diablo) for about 2 weeks now, its a year only but only has 2000km on the clock.

I'm not sure whether my bike has a problem or not so I'm seeking some help from you guys. The main problem I have with it is the way it revs from idle, it doesn't seem very smooth.

For example it doesn't matter if the bike is hot or cold when it is idling and I twist the throttle quickly the revs build up normal but when I release the throttle they seem to hang higher up and them drop down. Does that make sense? If not I can record a video for you.

Also now and again I will hear a backfire but its not coming from the exhaust but sounds like its coming from inside the airbox, is that normal?

The engine "ignition" light isn't on so the edu hasn't picked up a fault anywhere. Is there anything I can do to find out if there is a sensor problem somewhere.