you can see for yourself in the pics xulfiqar posted above.
if the engine in question has rocker arms and screws, its adjustable, ofcourse
on the other hand, if it has bucket type valve lifters, it isnt adjustable per se, because the lifter doesnt have any screws or anything adjustable in them. Unless the suzuki guys call cleaning out the buckets and checking it all as adjustment, it cant be done. they can be replaced, but not adjusted.
and if suzuki guys keep BS-ing you, dont take our word for it, search for it yourself...."hydraulic lifters"
this article explains the two types of lifters being talked about:
How Do Car Engine Lifters Work? | eHow.com
//youtu.be/http://www.youtube.com/watch?v=lorANZ1Tptw