Having a "tick" is actually normal. So the relative question is, how much "tick"?
I don't know your experience level with bikes, but if you are only familiar with auto engines or 2-strokes, then you may not have any problem with what you hear. Just remember that you are SUPPOSED to have some valve lash on your adjusters, therefore you will have some "tick". The valve train is totally mechanical, unlike the hydraulic lifters in a car or some bikes.
So, with that in mind, the only factors that are important are how well the engine runs, the location of the noise and how many miles are on the engine.
You are riding a Thumper and they have their own personality...
Besides, it's kinda like the clock on my shop wall. When it's really quiet, it also has a "tick"