suzuki df 90 year 2009 throttle idling problem


Oct 5, 2011
Hello I am new to this forum so please if someone can help I appreciate a lot ,I have a suzuki df 90 of year 2009 ,The motor was working and stalled and did not started ,I took it to our suzuki dealer in Malta and took off the fuel system line and injectors to check for dirt in all the fuel system but all was ok,we changed all fuel filters and when we started the engine for the first time after the service the engine did not wanted to start on neutral position ,then he gave some throttle and engine started,but revs. was 250 per min.,then he decided to rise the engine setting the screw near the air intake,and rise the revs to 500 rpm on idling.The engine now works ok but when engine is working on neutral position and I give throttle and put throttle back in a hurry the engine stalls and somethimes it starts after 3 cranks,is there any other things to check on idling position like idling valves or anything else,because the suzuki mechanic want to raise a little bit more the engine revs from the air intake screw again,but I am thinking this is not the right solution. And sorry if I make any spelling mistakes!