I don't know what most of the guys are saying, but I believe there is a very simple check. If you are experiencing the same problem on petrol as well, then there is a case of considering all the other factors. Otherwise, it is a simple case of gas adjustment!
Plugs and air filter are two main components... just get them checked. Gas setting may be fine... but good gas setting can only work if plugs and air filter are in order!
Other reason may be the idle RPM setting... which may be too low. Get this checked.