Numerous people have had problems with the tick over being variable and the bike often cutting out on the opening of the throttle.

After cleaning the injector (not hard to take it out) and making sure the coil is in tolerance and your fuel filter is decent, it is worth having a look around the throttle body to look for air leaks.

It's worth giving it a quick squirt down the venturi with carb cleaner but loose/cracked tubes and loose fastners are a good thing to check. check rubber tube to engine is not holed or cracked and also it is done up tightly. Then check the pipework around the throttle body.

The main offender is a lower tube on the LHS leading from the bottom of the airbox to the throttle body. give it a squeeze to see if it is cracked. the fastner on the throttle body is a low quality pinch ring. Throw this away and replace it with a good quality work screw fastner.

Hopefully that should sort you!