I would not worry to much mine did same thing after I serviced it. And I know what I am doing and did it to the letter. Even re did the oil change but same thing happened. But it never changed or did anything to the bike. Still did 1000s of miles on it. Just done the same service on my new xt660 and that one is spot on no noise. Have know idea why the other ticked for about 5 seconds after service but it did. Check the oil is coming out of the screw at the top of the oil filter housing just un screw it a bit run the bike and it should start to weep out the screw it back if it weeps out at least it’s pumping round right. You may want to ask did they put the oil in, in two stages. As off top of my head it’s 1.9 litres in first start bike rev/blip bike 5 or 6 times then turn off and add 0.6 litres that’s how the oil change should be done. Just check they did it that way. Not saying that would make any difference but there is a reason it should be done that way.also same as nicroc said it is almost impossible to check the oil level on the xt660 I will change to oil on my xt660 every 1000 miles like I did my old one. And put in the right amount from what te book says and that way I know it’s right also I check the amount that comes out so I know if there is any oil usage. And by changing my oil every 1000 miles I know my engine is being looked after right. I do my big bikes every 2000 miles.